IP Services Commands
Use the commands in this chapter to configure various IP services. For configuration information
and examples on IP services, refer to the "Configuring IP Services" chapter of the Network Protocols Configuration Guide, Part 1. access-class
To restrict incoming and outgoing connections between a particular virtual terminal line
(into a Cisco device) and the addresses in an access list, use the access-class line configuration command. To remove access restrictions, use the no form of this command.
access-class access-list-number {in | out}
no access-class access-list-number {in | out}
Syntax Description
Defaults
No access lists are defined.
Command Modes
Line configuration
Command History
Usage Guidelines
Remember to set identical restrictions on all the virtual terminal lines because a user can connect
to any of them.To display the access lists for a particular terminal line, use the show line EXEC command and specify the line number. Examples
The following example defines an access list that permits only hosts on network 192.89.55.0 to
connect to the virtual terminal ports on the router: access-list 12 permit 192.89.55.0 0.0.0.255 line 1 5 access-class 12 in
The following example defines an access list that denies connections to networks other than
network 36.0.0.0 on terminal lines 1 through 5: access-list 10 permit 36.0.0.0 0.255.255.255 line 1 5 access-class 10 out Related Commands
access-list (IP extended)
To define an extended IP access list, use the extended version of the access-list global configuration
command. To remove the access lists, use the no form of this command.
access-list access-list-number [dynamic dynamic-name [timeout minutes]] {deny | permit}
protocol source source-wildcard destination destination-wildcard [precedence precedence] [tos tos] [log | log-input] [fragments]
no access-list access-list-number
Internet Control Message Protocol (ICMP)
access-list access-list-number [dynamic dynamic-name [timeout minutes]] {deny | permit}
icmp source source-wildcard destination destination-wildcard [icmp-type | [[icmp-type icmp-code] | [icmp-message]] [precedence precedence] [tos tos] [log | log-input] [fragments]
Internet Group Management Protocol (IGMP)
access-list access-list-number [dynamic dynamic-name [timeout minutes]] {deny | permit}
igmp source source-wildcard destination destination-wildcard [igmp-type] [precedence precedence] [tos tos] [log | log-input] [fragments]
TCP
access-list access-list-number [dynamic dynamic-name [timeout minutes]] {deny | permit}
tcp source source-wildcard [operator port [port]] destination destination-wildcard [operator port [port]] [established] [precedence precedence] [tos tos] [log | log-input] [fragments]
User Datagram Protocol (UDP)
access-list access-list-number [dynamic dynamic-name [timeout minutes]] {deny | permit}
udp source source-wildcard [operator port [port]] destination destination-wildcard [operator port [port]] [precedence precedence] [tos tos] [log | log-input] [fragments]
Caution
 Enhancements to this command are backward compatible; migrating from releasesprior to Release 11.1 will convert your access lists automatically. However, releases prior to Release 11.1 are not upwardly compatible with these enhancements. Therefore, if you save an access list with these images and then use software prior to Release 11.1, the resulting access list will not be interpreted correctly. This could cause you severe security problems. Save your old configuration file before booting these images. Syntax Description
Defaults
An extended access list defaults to a list that denies everything. An extended access list is t
erminated by an implicit deny statement. Command Modes
Global configuration
Command History
Usage Guidelines
You can use access lists to control the transmission of packets on an interface,
control virtual terminal line access, and restrict contents of routing updates. The Cisco IOS software stops checking the extended access list after a match occurs. 
Note
After an access list is created initially, any subsequent additions(possibly entered from the terminal) are placed at the end of the list. In other words, you cannot selectively add or remove access list command lines from a specific access list.
The following is a list of precedence names:
Access List Processing of Fragments
The behavior of access-list entries regarding the use or lack of the fragments
keyword can be summarized as follows:
Be aware that you should not simply add the fragments keyword to every access list entry
because the first fragment of the IP packet is considered a nonfragment and is treated independently of the subsequent fragments. An initial fragment will not match an access list permit or deny entry that contains the fragments keyword, the packet is compared to the next access list entry, and so on, until it is either permitted or denied by an access list entry that does not contain the fragments keyword. Therefore, you may need two access list entries for every deny entry. The first deny entry of the pair will not include the fragments keyword, and applies to the initial fragment. The second deny entry of the pair will include the fragments keyword and applies to the subsequent fragments. In the cases where there are multiple deny access list entries for the same host but with different Layer 4 ports, a single deny access-list entry with the fragments keyword for that host is all that needs to be added. Thus all the fragments of a packet are handled in the same manner by the access list.
Packet fragments of IP datagrams are considered individual packets and each counts
individually as a packet in access list accounting and access list violation counts.
Note
The fragments keyword cannot solve all cases involving access lists and IP fragments.
Fragments and Policy Routing
Fragmentation and the fragment control feature affect policy routing if the policy routing is based
on the match ip address command and the access list had entries that match on Layer 4 through 7 information. It is possible that noninitial fragments pass the access list and are policy routed, even if the first fragment was not policy routed or the reverse.
By using the fragments keyword in access list entries as described earlier,
a better match between the action taken for initial and noninitial fragments can be made and . it is more likely policy routing will occur as intended. Examples
In the following example, serial interface 0 is part of a Class B network with the address 128.88.0.0,
and the mail host's address is 128.88.1.2. The keyword established is used only for the TCP protocol to indicate an established connection. A match occurs if the TCP datagram has the ACK or RST bits set, which indicate that the packet belongs to an existing connection. access-list 102 permit tcp 0.0.0.0 255.255.255.255 128.88.0.0 0.0.255.255 established access-list 102 permit tcp 0.0.0.0 255.255.255.255 128.88.1.2 0.0.0.0 eq 25 interface serial 0 ip access-group 102 in
The following example also permit Domain Naming System (DNS) packets and ICMP echo
and echo reply packets: access-list 102 permit tcp any 128.88.0.0 0.0.255.255 established access-list 102 permit tcp any host 128.88.1.2 eq smtp access-list 102 permit tcp any any eq domain access-list 102 permit udp any any eq domain access-list 102 permit icmp any any echo access-list 102 permit icmp any any echo-reply
The following examples show how wildcard bits are used to indicate the bits of the prefix or
mask that are relevant. They are similar to the bitmasks that are used with normal access lists. Prefix/mask bits corresponding to wildcard bits set to 1 are ignored during comparisons and prefix/mask bits corresponding to wildcard bits set to 0 are used in comparison.
In the following example, permit 192.108.0.0 255.255.0.0 but deny any more specific routes
of 192.108.0.0 (including 192.108.0.0 255.255.255.0). access-list 101 permit ip 192.108.0.0 0.0.0.0 255.255.0.0 0.0.0.0 access-list 101 deny ip 192.108.0.0 0.0.255.255 255.255.0.0 0.0.255.255
In the following example, permit 131.108.0/24 but deny 131.108/16 and
all other subnets of 131.108.0.0. access-list 101 permit ip 131.108.0.0 0.0.0.0 255.255.255.0 0.0.0.0 access-list 101 deny ip 131.108.0.0 0.0.255.255 255.255.0.0 0.0.255.255 Related Commands
access-list (IP standard)
To define a standard IP access list, use the standard version of the access-list
global configuration command. To remove a standard access lists, use the no form of this command.
access-list access-list-number {deny | permit} source [source-wildcard] [log]
no access-list access-list-number
Caution
Enhancements to this command are backward compatible; migrating fromreleases prior to Release 10.3 will convert your access lists automatically. However, releases prior to Release 10.3 are not upwardly compatible with these enhancements. Therefore, if you save an access list with these images and then use software prior to Release 10.3, the resulting access list will not be interpreted correctly. This could cause you severe security problems. Save your old configuration file before booting these images. Syntax Description
Defaults
The access list defaults to an implicit deny statement for everything.
The access list is always terminated by an implicit deny statement for everything. Command Modes
Global configuration
Command History
Usage Guidelines
Plan your access conditions carefully and be aware of the implicit deny statement at
the end of the access list.
You can use access lists to control the transmission of packets on an interface,
control virtual terminal line access, and restrict the contents of routing updates.
Use the show access-lists EXEC command to display the contents of all access lists.
Use the show ip access-list EXEC command to display the contents of one access list.
Examples
The following example of a standard access list allows access for only those hosts on
the three specified networks. The wildcard bits apply to the host portions of the network addresses. Any host with a source address that does not match the access list statements will be rejected. access-list 1 permit 192.5.34.0 0.0.0.255 access-list 1 permit 128.88.0.0 0.0.255.255 access-list 1 permit 36.0.0.0 0.255.255.255 ! (Note: all other access implicitly denied)
The following example of a standard access list allows access for devices with
IP addresses in the range 10.29.2.64 to 10.29.2.127. All packets with a source address not in this range will be rejected. access-list 1 permit 10.29.2.64 0.0.0.63 ! (Note: all other access implicitly denied)
To specify a large number of individual addresses more easily,
you can omit the wildcard if it is all zeros. Thus, the following two configuration commands are identical in effect: access-list 2 permit 36.48.0.3 access-list 2 permit 36.48.0.3 0.0.0.0 Related Commands
clear access-list counters
To clear the counters of an access list, use the clear access-list counters EXEC command.
clear access-list counters {access-list-number | name}
Syntax Description
Command Modes
EXEC
Command History
Usage Guidelines
Some access lists keep counters that count the number of packets that pass each line of an access list.
The show access-lists command displays the counters as a number of matches. Use the clear access-list counters command to restart the counters for a particular access list to 0. Examples
The following example clears the counters for access list 101:
clear access-list counters 101 Related Commands
clear ip accounting
To clear the active or checkpointed database when IP accounting is enabled,
use the clear ip accounting EXEC command.
clear ip accounting [checkpoint]
Syntax Description
Command Modes
EXEC
Command History
Usage Guidelines
You can also clear the checkpointed database by issuing the clear ip accounting command
twice in succession. Examples
The following example clears the active database when IP accounting is enabled:
clear ip accounting Related Commands
clear ip drp
To clear all statistics being collected on Director Response Protocol (DRP) requests and replies,
use the clear ip drp EXEC command.
clear ip drp
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Examples
The following example clears all DRP statistics:
clear ip drp Related Commands
clear tcp statistics
To clear TCP statistics, use the clear tcp statistics EXEC command.
clear tcp statistics
Syntax Description
This command has no arguments or keywords.
Command Modes
Privileged EXEC
Command History
Examples
The following example clears all TCP statistics:
clear tcp statistics Related Commands
deny (IP)
To set conditions for a named IP access list, use the deny access-list configuration command.
To remove a deny condition from an access list, use the no form of this command.
deny {source [source-wildcard] | any} [log]
no deny {source [source-wildcard] | any}
deny protocol source source-wildcard destination destination-wildcard [precedence precedence]
[tos tos] [log] [fragments]
no deny protocol source source-wildcard destination destination-wildcard
ICMP
deny icmp source source-wildcard destination destination-wildcard
[icmp-type [icmp-code] | icmp-message] [precedence precedence] [tos tos] [log] [fragments]
IGMP
deny igmp source source-wildcard destination destination-wildcard [igmp-type]
[precedence precedence] [tos tos] [log] [fragments]
TCP
deny tcp source source-wildcard [operator port [port]] destination destination-wildcard
[operator port [port]] [established] [precedence precedence] [tos tos] [log] [fragments]
UDP
deny udp source source-wildcard [operator port [port]] destination destination-wildcard
[operator port [port]] [precedence precedence] [tos tos] [log] [fragments] Syntax Description
Defaults
There is no specific condition under which a packet is denied passing the named access list.
Command Modes
Access-list configuration
Command History
Usage Guidelines
Use this command following the ip access-list command to specify conditions under which
a packet cannot pass the named access list.
Access List Processing of Fragments
The behavior of access-list entries regarding the use or lack of the fragments
keyword can be summarized as follows:
Be aware that you should not simply add the fragments keyword to every access list entry because
the first fragment of the IP packet is considered a nonfragment and is treated independently of the subsequent fragments. An initial fragment will not match an access list permit or deny entry that contains the fragments keyword, the packet is compared to the next access list entry, and so on, until it is either permitted or denied by an access list entry that does not contain the fragments keyword. Therefore, you may need two access list entries for every deny entry. The first deny entry of the pair will not include the fragments keyword, and applies to the initial fragment. The second deny entry of the pair will include the fragments keyword and applies to the subsequent fragments. In the cases where there are multiple deny access list entries for the same host but with different Layer 4 ports, a single deny access-list entry with the fragments keyword for that host is all that needs to be added. Thus all the fragments of a packet are handled in the same manner by the access list.
Packet fragments of IP datagrams are considered individual packets and each counts individually
as a packet in access list accounting and access list violation counts.
Note
The fragments keyword cannot solve all cases involving access lists and IP fragments.
Fragments and Policy Routing
Fragmentation and the fragment control feature affect policy routing if the policy routing is based on the match ip address command and the access list had entries that match on Layer 4 through 7 information. It is possible that noninitial fragments pass the access list and are policy routed, even if the first fragment was not policy routed or the reverse.
By using the fragments keyword in access list entries as described earlier, a better match between the action taken for initial and noninitial fragments can be made and it is more likely policy routing will occur as intended.
Examples
The following example sets a deny condition for a standard access list named Internetfilter:
ip access-list standard Internetfilter deny 192.5.34.0 0.0.0.255 permit 128.88.0.0 0.0.255.255 permit 36.0.0.0 0.255.255.255 ! (Note: all other access implicitly denied) Related Commands
dynamic
To define a named, dynamic, IP access list, use the dynamic access-list configuration command. To remove the access lists, use the no form of this command.
dynamic dynamic-name [timeout minutes] {deny | permit} protocol source source-wildcard destination destination-wildcard [precedence precedence] [tos tos] [log] [fragments]
no dynamic dynamic-name
ICMP
dynamic dynamic-name [timeout minutes] {deny | permit} icmp source source-wildcard destination destination-wildcard [icmp-type [icmp-code] | icmp-message] [precedence precedence] [tos tos] [log] [fragments]
IGMP
dynamic dynamic-name [timeout minutes] {deny | permit} igmp source source-wildcard destination destination-wildcard [igmp-type] [precedence precedence] [tos tos] [log] [fragments]
TCP
dynamic dynamic-name [timeout minutes] {deny | permit} tcp source source-wildcard [operator port [port]] destination destination-wildcard [operator port [port]] [established] [precedence precedence] [tos tos] [log] [fragments]
UDP
dynamic dynamic-name [timeout minutes] {deny | permit} udp source source-wildcard [operator port [port]] destination destination-wildcard [operator port [port]] [precedence precedence] [tos tos] [log] [fragments]
Caution
Named IP access lists will not be recognized by any software release prior to Cisco IOS Release 11.2. Syntax Description
Defaults
An extended access list defaults to a list that denies everything. An extended access list is terminated by an implicit deny statement.
Command Modes
Access-list configuration
Command History
Usage Guidelines
You can use named access lists to control the transmission of packets on an interface and restrict contents of routing updates. The Cisco IOS software stops checking the extended access list after a match occurs.
Fragmented IP packets, other than the initial fragment, are immediately accepted by any extended IP access list. Extended access lists used to control virtual terminal line access or restrict contents of routing updates must not match against the TCP source port, the type of service value, or the packet's precedence.
Note
After an access list is created initially, any subsequent additions (possibly entered from the terminal) are placed at the end of the list. In other words, you cannot selectively add or remove access list command lines from a specific access list.
The following is a list of precedence names:
•
critical
•
flash
•
flash-override
•
immediate
•
internet
•
network
•
priority
•
routine
The following is a list of type of service (TOS) names:
•
max-reliability
•
max-throughput
•
min-delay
•
min-monetary-cost
•
normal
The following is a list of ICMP message type names and ICMP message type and code names:
•
administratively-prohibited
•
alternate-address
•
conversion-error
•
dod-host-prohibited
•
dod-net-prohibited
•
echo
•
echo-reply
•
general-parameter-problem
•
host-isolated
•
host-precedence-unreachable
•
host-redirect
•
host-tos-redirect
•
host-tos-unreachable
•
host-unknown
•
host-unreachable
•
information-reply
•
information-request
•
mask-reply
•
mask-request
•
mobile-redirect
•
net-redirect
•
net-tos-redirect
•
net-tos-unreachable
•
net-unreachable
•
network-unknown
•
no-room-for-option
•
option-missing
•
packet-too-big
•
parameter-problem
•
port-unreachable
•
precedence-unreachable
•
protocol-unreachable
•
reassembly-timeout
•
redirect
•
router-advertisement
•
router-solicitation
•
source-quench
•
source-route-failed
•
time-exceeded
•
timestamp-reply
•
timestamp-request
•
traceroute
•
ttl-exceeded
•
unreachable
The following is a list of IGMP message names:
•
dvmrp
•
host-query
•
host-report
•
pim
•
trace
The following is a list of TCP port names that can be used instead of port numbers. Refer to the current Assigned Numbers RFC to find a reference to these protocols. Port numbers corresponding to these protocols can also be found by typing a ? in the place of a port number.
•
bgp
•
chargen
•
daytime
•
discard
•
domain
•
echo
•
finger
•
ftp
•
ftp-data
•
gopher
•
hostname
•
irc
•
klogin
•
kshell
•
lpd
•
nntp
•
pop2
•
pop3
•
smtp
•
sunrpc
•
syslog
•
tacacs-ds
•
talk
•
telnet
•
time
•
uucp
•
whois
•
www
The following is a list of UDP port names that can be used instead of port numbers. Refer to the current Assigned Numbers RFC to find a reference to these protocols. Port numbers corresponding to these protocols can also be found by typing a ? in the place of a port number.
•
biff
•
bootpc
•
bootps
•
discard
•
dns
•
dnsix
•
echo
•
mobile-ip
•
nameserver
•
netbios-dgm
•
netbios-ns
•
ntp
•
rip
•
snmp
•
snmptrap
•
sunrpc
•
syslog
•
tacacs-ds
•
talk
•
tftp
•
time
•
who
•
xdmcp
Access List Processing of Fragments
The behavior of access-list entries regarding the use or lack of the fragments keyword can be summarized as follows:
Be aware that you should not simply add the fragments keyword to every access list entry because the first fragment of the IP packet is considered a nonfragment and is treated independently of the subsequent fragments. An initial fragment will not match an access list permit or deny entry that contains the fragments keyword, the packet is compared to the next access list entry, and so on, until it is either permitted or denied by an access list entry that does not contain the fragments keyword. Therefore, you may need two access list entries for every deny entry. The first deny entry of the pair will not include the fragments keyword, and applies to the initial fragment. The second deny entry of the pair will include the fragments keyword and applies to the subsequent fragments. In the cases where there are multiple deny access list entries for the same host but with different Layer 4 ports, a single deny access-list entry with the fragments keyword for that host is all that needs to be added. Thus all the fragments of a packet are handled in the same manner by the access list.
Packet fragments of IP datagrams are considered individual packets and each counts individually as a packet in access list accounting and access list violation counts.
Note
The fragments keyword cannot solve all cases involving access lists and IP fragments.
Fragments and Policy Routing
Fragmentation and the fragment control feature affect policy routing if the policy routing is based on the match ip address command and the access list had entries that match on Layer 4 through 7 information. It is possible that noninitial fragments pass the access list and are policy routed, even if the first fragment was not policy routed or the reverse.
By using the fragments keyword in access list entries as described earlier, a better match between the action taken for initial and noninitial fragments can be made and it is more likely policy routing will occur as intended.
Examples
The following example defines a dynamic access list named washington:
ip access-group washington in ! ip access-list extended washington dynamic testlist timeout 5 permit ip any any permit tcp any host 185.302.21.2 eq 23 Related Commands
ip access-group
To control access to an interface, use the ip access-group interface configuration command. To remove the specified access group, use the no form of this command.
ip access-group {access-list-number | name}{in | out}
no ip access-group {access-list-number | name}{in | out}
Syntax Description
Defaults
No access list is applied to the interface.
Command Modes
Interface configuration
Command History
Usage Guidelines
Access lists are applied on either outbound or inbound interfaces. For standard inbound access lists, after receiving a packet, the Cisco IOS software checks the source address of the packet against the access list. For extended access lists, the router also checks the destination access list. If the access list permits the address, the software continues to process the packet. If the access list rejects the address, the software discards the packet and returns an ICMP Host Unreachable message.
For standard outbound access lists, after receiving and routing a packet to a controlled interface, the software checks the source address of the packet against the access list. For extended access lists, the router also checks the destination access list. If the access list permits the address, the software transmits the packet. If the access list rejects the address, the software discards the packet and returns an ICMP Host Unreachable message.
If the specified access list does not exist, all packets are passed.
When you enable outbound access lists, you automatically disable autonomous switching for that interface.When you enable input access lists on any cBus or CxBus interface, you automatically disable autonomous switching for all interfaces (with one exception—an SSE configured with simple access lists can still switch packets, on output only).
Examples
The following example applies list 101 on packets outbound from Ethernet interface 0:
interface ethernet 0 ip access-group 101 out Related Commands
ip access-list
To define an IP access list by name, use the ip access-list global configuration command. To remove a named IP access lists, use the no form of this command.
ip access-list {standard | extended} name
no ip access-list {standard | extended} name
Caution
Named access lists will not be recognized by any software release prior to Cisco IOS Release 11.2. Syntax Description
Defaults
No named IP access list is defined.
Command Modes
Global configuration
Command History
Usage Guidelines
Use this command to configure a named IP access list as opposed to a numbered IP access list. This command will take you into access-list configuration mode, where you must define the denied or permitted access conditions with the deny and permit commands.
Specifying standard or extended with the ip access-list command determines the prompt you get when you enter access-list configuration mode.
Use the ip access-group command to apply the access-list to an interface.
Named access lists are not compatible with Cisco IOS releases prior to Release 11.2.
Examples
The following example defines a standard access list named Internetfilter:
ip access-list standard Internetfilter permit 192.5.34.0 0.0.0.255 permit 128.88.0.0 0.0.255.255 permit 36.0.0.0 0.255.255.255 ! (Note: all other access implicitly denied) Related Commands
ip accounting
To enable IP accounting on an interface, use the ip accounting interface configuration command. To disable IP accounting, use the no form of this command.
ip accounting [access-violations] [output-packets]
no ip accounting [access-violations] [output-packets]
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
The ip accounting command records the number of bytes (IP header and data) and packets switched through the system on a source and destination IP address basis. Only transit IP traffic is measured and only on an outbound basis; traffic generated by the router access server or terminating in this device is not included in the accounting statistics. Use the show ip accounting command to display the active accounting database, and traffic coming from a remote site and transiting through a router.
If you specify the access-violations keyword, ip accounting provides information identifying IP traffic that fails IP access lists. Identifying IP source addresses that violate IP access lists alerts you to possible attempts to breach security. The data might also indicate that you should verify IP access list configurations.
To receive a logging message on the console when an extended access list entry denies a packet access (to log violations), you must include the log keyword in the access-list (IP extended) or access-list (IP standard) command.
Statistics are accurate even if IP fast switching or IP access lists are being used on the interface.
IP accounting disables autonomous switching, SSE switching, and distributed switching (dCEF) on the interface. IP accounting will cause packets to be switched on the Route Switch Processor (RSP) instead of the Versatile Interface Processor (VIP), which can cause performance degradation.
Examples
The following example enables IP accounting on Ethernet interface 0:
interface ethernet 0 ip accounting Related Commands
ip accounting-list
To define filters to control the hosts for which IP accounting information is kept, use the ip accounting-list global configuration command. To remove a filter definition, use the no form of this command.
ip accounting-list ip-address wildcard
no ip accounting-list ip-address wildcard
Syntax Description
Defaults
No filters are defined.
Command Modes
Global configuration
Command History
Usage Guidelines
The source and destination address of each IP datagram is logically ANDed with the wildcard bits and compared with the ip-address. If there is a match, the information about the IP datagram will be entered into the accounting database. If there is no match, the IP datagram is considered a transit datagram and will be counted according to the setting of the ip accounting-transits global configuration command.
Examples
The following example adds all hosts with IP addresses beginning with 192.31 to the list of hosts for which accounting information will be kept:
ip accounting-list 192.31.0.0 0.0.255.255 Related Commands
ip accounting-threshold
To set the maximum number of accounting entries to be created, use the ip accounting-threshold global configuration command. To restore the default number of entries, use the no form of this command.
ip accounting-threshold threshold
no ip accounting-threshold threshold
Syntax Description
Defaults
512 entries
Command Modes
Global configuration
Command History
Usage Guidelines
The accounting threshold defines the maximum number of entries (source and destination address pairs) that the software accumulates, preventing IP accounting from possibly consuming all available free memory. This level of memory consumption could occur in a router that is switching traffic for many hosts. Overflows will be recorded; see the monitoring commands for display formats.
The default accounting threshold of 512 entries results in a maximum table size of 12,928 bytes. Active and checkpointed tables can reach this size independently.
Examples
The following example sets the IP accounting threshold to only 500 entries:
ip accounting-threshold 500 Related Commands
ip accounting-transits
To control the number of transit records that are stored in the IP accounting database, use the ip accounting-transits global configuration command. To return to the default number of records, use the no form of this command.
ip accounting-transits count
no ip accounting-transits
Syntax Description
Defaults
0
Command Modes
Global configuration
Command History
Usage Guidelines
Transit entries are those that do not match any of the filters specified by ip accounting-list global configuration commands. If no filters are defined, no transit entries are possible.
To maintain accurate accounting totals, the Cisco IOS software maintains two accounting databases: an active and a checkpointed database.
Examples
The following example specifies that no more than 100 transit records are stored:
ip accounting-transits 100 Related Commands
ip accounting mac-address
To enable IP accounting on a LAN interface based on the source and destination MAC address, use the ip accounting mac-address interface configuration command. To disable IP accounting based on the source and destination MAC address, use the no form of this command.
ip accounting mac-address {input | output]
no ip accounting mac-address {input | output]
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
This feature is supported on Ethernet, FastEthernet, and FDDI interfaces.
To display the MAC accounting information, use the show interface mac EXEC command.
MAC address accounting provides accounting information for IP traffic based on the source and destination MAC address on LAN interfaces. This calculates the total packet and byte counts for a LAN interface that receives or sends IP packets to or from a unique MAC address. It also records a timestamp for the last packet received or sent. With MAC address accounting, you can determine how much traffic is being sent to and/or received from various peers at NAPS/peering points.
Examples
The following example enables IP accounting based on the source and destination MAC address for received and transmitted packets:
interface ethernet 4/0/0 ip accounting mac-address input ip accounting mac-address output Related Commands
ip accounting precedence
To enable IP accounting on any interface based on IP precedence, use the ip accounting precedence interface configuration command. To disable IP accounting based on IP precedence, use the no form of this command.
ip accounting precedence {input | output]
no ip accounting precedence {input | output]
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
To display IP precedence accounting information, use the show interface precedence EXEC command.
The precedence accounting feature provides accounting information for IP traffic, summarized by IP precedence value(s). This feature calculates the total packet and byte counts for an interface that receives or sends IP packets and sorts the results based on IP precedence. This feature is supported on all interfaces and subinterfaces and supports CEF, dCEF, flow, and optimum switching.
Examples
The following example enables IP accounting based on IP precedence for received and transmitted packets:
interface ethernet 4/0/0 ip accounting precedence input ip accounting precedence output Related Commands
ip drp access-group
To control the sources of Director Response Protocol (DRP) queries to the DRP Server Agent, use the ip drp access-group global configuration command. To remove the access list, use the no form of this command.
ip drp access-group access-list-number
no ip drp access-group access-list-number
Syntax Description
Defaults
The DRP Server Agent will answer all queries.
Command Modes
Global configuration
Command History
Usage Guidelines
This command applies an access list to the interface, thereby controlling who can send queries to the DRP Server Agent.
If both an authentication key chain and an access group have been specified, both security measures must permit access before a request is processed.
Examples
The following example configures access list 1, which permits only queries from the host at 33.45.12.4:
access-list 1 permit 33.45.12.4 ip drp access-group 1 Related Commands
ip drp authentication key-chain
To configure authentication on the DRP Server Agent for DistributedDirector, use the ip drp authentication key-chain global configuration command. To remove the key chain, use the no form of this command.
ip drp authentication key-chain name-of-chain
no ip drp authentication key-chain name-of-chain
Syntax Description
Defaults
No authentication is configured for the DRP Server Agent.
Command Modes
Global configuration
Command History
Usage Guidelines
When a key chain and key are configured, the key is used to authenticate all Director Response Protocol requests and responses. The active key on the DRP Server Agent must match the active key on the primary agent. Use the key and key-string commands to configure the key.
Examples
The following example configures a key chain named ddchain:
ip drp authentication key-chain ddchain Related Commands
ip drp server
To enable the Director Response Protocol (DRP) Server Agent that works with DistributedDirector, use the ip drp server global configuration command. To disable the DRP Server Agent, use the no form of this command.
ip drp server
no ip drp server
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Global configuration
Command History
Examples
The following example enables the DRP Server Agent:
ip drp server Related Commands
ip icmp rate-limit unreachable
To have the Cisco IOS software limit the rate that Internet Control Message Protocol (ICMP) destination unreachable messages are generated, use the ip icmp rate-limit unreachable global configuration command. To remove the rate limit, use the no form of this command.
ip icmp rate-limit unreachable [df] milliseconds
no ip icmp rate-limit unreachable [df]
Syntax Description
Defaults
The default value is one ICMP destination unreachable message per 500 milliseconds.
Command Modes
Global configuration
Command History
Usage Guidelines
The no ip icmp rate-limit unreachable command turns off the previously configured rate limit. To re-set the rate limit to its default value, use the default ip icmp rate-limit unreachable command.
The Cisco IOS software maintains two timers: one for general destination unreachable messages and one for DF destination unreachable messages. Both share the same time limits and defaults. If the df option is not configured, the ip icmp rate-limit unreachable command sets the time values for DF destination unreachable messages. If the df option is configured, its time values remain independent from those of general destination unreachable messages.
Examples
The following example sets the rate of the ICMP destination unreachable message to one message every 10 milliseconds:
ip icmp rate-limit unreachable 10
The following example turns off the previously configured rate limit:
no ip icmp rate-limit unreachable
The following example sets the rate limit back to the default:
default ip icmp rate-limit unreachable ip icmp redirect
To control the type of Internet Control Message Protocol (ICMP) redirect message that is sent by the Cisco IOS software, use the ip icmp redirect command in global configuration mode. To set the value back to the default, use the no form of this command.
ip icmp redirect [host | subnet]
no ip icmp redirect [host | subnet]
Syntax Description
Defaults
The router will send ICMP subnet redirect messages.
Because the ip icmp redirect subnet command is the default, the command will not be displayed in the configuration.
Command Modes
Global configuration
Command History
Usage Guidelines
An ICMP redirect message can be generated by a router when a packet is received and transmitted on the same interface. In this situation, the router will forward the original packet and send a ICMP redirect message back to the sender of the original packet. This behavior allows the sender to bypass the router and forward future packets directly to the destination (or a router closer to the destination).
There are two types of ICMP redirect messages: redirect for a host address or redirect for an entire subnet.
The ip icmp redirect command determines the type of ICMP redirects sent by the system and is configured on a per system basis. Some hosts do not understand ICMP subnet redirects and need the router to send out ICMP host redirects. Use the ip icmp redirect host command to have the router send out ICMP host redirects. Use the ip icmp redirect subnet command to set the value back to the default, which is to send subnet redirects.
To prevent the router from sending ICMP redirects, use the no ip redirects interface configuration command.
Examples
The following example enables the router to send out ICMP host redirects:
ip icmp redirect hosts
The following example sets the value back to the default, which is subnet redirects:
ip icmp redirect subnet Related Commands
ip mask-reply
To have the Cisco IOS software respond to Internet Control Message Protocol (ICMP) mask requests by sending ICMP Mask Reply messages, use the ip mask-reply interface configuration command. To disable this function, use the no form of this command.
ip mask-reply
no ip mask-reply
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Interface configuration
Command History
Examples
The following example enables the sending of ICMP Mask Reply messages on Ethernet interface 0:
interface ethernet 0 ip address 131.108.1.0 255.255.255.0 ip mask-reply ip mtu
To set the maximum transmission unit (MTU) size of IP packets sent on an interface, use the ip mtu interface configuration command. To restore the default MTU size, use the no form of this command.
ip mtu bytes
no ip mtu
Syntax Description
Defaults
Minimum is 128 bytes; maximum depends on interface medium.
Command Modes
Interface configuration
Command History
Usage Guidelines
If an IP packet exceeds the MTU set for the interface, the Cisco IOS software will fragment it.
All devices on a physical medium must have the same protocol MTU in order to operate.
Note
Changing the MTU value (with the mtu interface configuration command) can affect the IP MTU value. If the current IP MTU value is the same as the MTU value, and you change the MTU value, the IP MTU value will be modified automatically to match the new MTU. However, the reverse is not true; changing the IP MTU value has no effect on the value for the mtu command. Examples
The following example sets the maximum IP packet size for the first serial interface to 300 bytes:
interface serial 0 ip mtu 300 Related Commands
ip redirects
To enable the sending of ICMP Redirect messages if the Cisco IOS software is forced to resend a packet through the same interface on which it was received, use the ip redirects interface configuration command. To disable the sending of redirect messages, use the no form of this command.
ip redirects
no ip redirects
Syntax Description
This command has no arguments or keywords.
Defaults
Enabled, unless Hot Standby Router Protocol is configured
Command Modes
Interface configuration
Command History
Usage Guidelines
If the Hot Standby Router Protocol is configured on an interface, ICMP Redirect messages are disabled by default for the interface.
Examples
The following example enables the sending of ICMP Redirect messages on Ethernet interface 0:
interface ethernet 0 ip redirects Related Commands
ip source-route
To allow the Cisco IOS software to handle IP datagrams with source routing header options, use the ip source-route global configuration command. To have the software discard any IP datagram containing a source-route option, use the no form of this command.
ip source-route
no ip source-route
Syntax Description
This command has no arguments or keywords.
Defaults
Enabled
Command Modes
Global configuration
Command History
Examples
The following example enables the handling of IP datagrams with source routing header options:
ip source-route Related Commands
ip tcp chunk-size
To alter the TCP maximum read size for Telnet or rlogin, use the ip tcp chunk-size global configuration command. To restore the default value, use the no form of this command.
ip tcp chunk-size characters
no ip tcp chunk-size
Syntax Description
Defaults
0, which Telnet and rlogin interpret as the largest possible 32-bit positive number.
Command Modes
Global configuration
Command History
Usage Guidelines
It is unlikely you will need to change the default value.
Examples
The following example sets the maximum TCP read size to 64000 bytes:
ip tcp chunk-size 64000 ip tcp compression-connections
To specify the total number of header compression connections that can exist on an interface, use the ip tcp compression-connections interface configuration command. To restore the default, use the no form of this command.
ip tcp compression-connections number
no ip tcp compression-connections number
Syntax Description
Defaults
16 connections
Command Modes
Interface configuration
Command History
Usage Guidelines
You should configure one connection for each TCP connection through the specified interface.
Each connection sets up a compression cache entry, so you are in effect specifying the maximum number of cache entries and the size of the cache. Too few cache entries for the specified interface can lead to degraded performance, while too many cache entries can lead to wasted memory.
Note
Both ends of the serial connection must use the same number of cache entries. Examples
The following example sets the first serial interface for header compression with a maximum of ten cache entries:
interface serial 0 ip tcp header-compression ip tcp compression-connections 10 Related Commands
ip tcp header-compression
To enable TCP header compression, use the ip tcp header-compression interface configuration command. To disable compression, use the no form of this command.
ip tcp header-compression [passive]
no ip tcp header-compression [passive]
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
You can compress the headers of your TCP/IP packets in order to reduce the size of your packets. TCP header compression is supported on serial lines using Frame Relay, HDLC or Point-to-Point (PPP) encapsulation. You must enable compression on both ends of a serial connection. RFC 1144 specifies the compression process. Compressing the TCP header can speed up Telnet connections dramatically. In general, TCP header compression is advantageous when your traffic consists of many small packets, not for traffic that consists of large packets. Transaction processing (usually using terminals) tends to use small packets while file transfers use large packets. This feature only compresses the TCP header, so it has no effect on UDP packets or other protocol headers.
When compression is enabled, fast switching is disabled. This means that fast interfaces like T1 can overload the router. Consider your network's traffic characteristics before using this command.
Examples
The following example sets the first serial interface for header compression with a maximum of ten cache entries:
interface serial 0 ip tcp header-compression ip tcp compression-connections 10 Related Commands
ip tcp path-mtu-discovery
To enable Path MTU Discovery for all new TCP connections from the router, use the ip tcp path-mtu-discovery global configuration command. To disable the function, use the no form of this command.
ip tcp path-mtu-discovery [age-timer {minutes | infinite}]
no ip tcp path-mtu-discovery [age-timer {minutes | infinite}]
Syntax Description
Defaults
Disabled. If enabled, default minutes is 10 minutes.
Command Modes
Global configuration
Command History
Usage Guidelines
Path MTU Discovery is a method for maximizing the use of available bandwidth in the network between the end points of a TCP connection. It is described in RFC 1191. Existing connections are not affected when this feature is turned on or off.
Customers using TCP connections to move bulk data between systems on distinct subnets would benefit most by enabling this feature. This might include customers using RSRB with TCP encapsulation, STUN, X.25 Remote Switching (also known as XOT, or X.25 over TCP), and some protocol translation configurations.
The age timer is a time interval for how often TCP re-estimates the Path MTU with a larger MSS. By using the age timer, TCP Path MTU becomes a dynamic process. If MSS used for the connection is smaller than what the peer connection can handle, a larger MSS is tried every time the age timer expires. The discovery process is stopped when either the send MSS is as large as the peer negotiated, or the user has disabled the timer on the router. You can turn off the age-timer by setting it to infinite.
Examples
The following example enables Path MTU Discovery:
ip tcp path-mtu-discovery ip tcp queuemax
To alter the maximum TCP outgoing queue per connection, use the ip tcp queuemax global configuration command. To restore the default value, use the no form of this command.
ip tcp queuemax packets
no ip tcp queuemax
Syntax Description
Defaults
The default value is 5 segments if the connection has a TTY associated with it. If there is no TTY associated with it, the default value is 20 segments.
Command Modes
Global configuration
Command History
Usage Guidelines
Changing the default value changes the 5 segments, not the 20 segments.
Examples
The following example sets the maximum TCP outgoing queue to 10 packets:
ip tcp queuemax 10 ip tcp selective-ack
To enable TCP selective acknowledgment, use the ip tcp selective-ack global configuration command. To disable TCP selective acknowledgment, use the no form of this command.
ip tcp selective-ack
no ip tcp selective-ack
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Global configuration
Command History
Usage Guidelines
TCP might not experience optimal performance if multiple packets are lost from one window of data. With the limited information available from cumulative acknowledgments, a TCP sender can learn about only one lost packet per round trip time. An aggressive sender could retransmit packets early, but such retransmitted segments might have already been successfully received.
The TCP selective acknowledgment mechanism helps overcome these limitations. The receiving TCP returns selective acknowledgment packets to the sender, informing the sender about data that has been received. The sender can then retransmit only the missing data segments.
TCP selective acknowledgment improves overall performance. The feature is used only when multiple packets drop from a TCP window. There is no performance impact when the feature is enabled but not used.
This command becomes effective only on new TCP connections opened after the feature is enabled.
This feature must be disabled if you want TCP header compression. You might disable this feature if you have severe TCP problems.
Refer to RFC 2018 for more detailed information on TCP selective acknowledgment.
Examples
The following example enables the router to send and receive TCP selective acknowledgments:
ip tcp selective-ack Related Commands
ip tcp synwait-time
To set a period of time the Cisco IOS software waits while attempting to establish a TCP connection before it times out, use the ip tcp synwait-time global configuration command. To restore the default time, use the no form of this command.
ip tcp synwait-time seconds
no ip tcp synwait-time seconds
Syntax Description
Defaults
30 seconds
Command Modes
Global configuration
Command History
Usage Guidelines
In versions previous to Cisco IOS software 10.0, the system would wait a fixed 30 seconds when attempting to establish a TCP connection. If your network contains Public Switched Telephone Network (PSTN) dial-on-demand routing (DDR), the call setup time may exceed 30 seconds. This amount of time is not sufficient in networks that have dial-up asynchronous connections because it will affect your ability to Telnet over the link (from the router) if the link must be brought up. If you have this type of network, you might want to set this value to the UNIX value of 75.
Because this is a host parameter, it does not pertain to traffic going through the router, just for traffic originated at this device. Because UNIX has a fixed 75-second timeout, hosts are unlikely to see this problem.
Examples
The following example configures the Cisco IOS software to continue attempting to establish a TCP connection for 180 seconds:
ip tcp synwait-time 180 ip tcp timestamp
To enable TCP timestamp, use the ip tcp timestamp global configuration command. To disable TCP timestamp, use the no form of this command.
ip tcp timestamp
no ip tcp timestamp
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Global configuration
Command History
Usage Guidelines
TCP timestamp improves round-trip time estimates. Refer to RFC 1323 for more detailed information on TCP timestamp.
This feature must be disabled if you want to use TCP header compression.
Examples
The following example enables the router to send TCP timestamps:
ip tcp timestamp Related Commands
ip tcp window-size
To alter the TCP window size, use the ip tcp window-size global configuration command. To restore the default value, use the no form of this command.
ip tcp window-size bytes
no ip tcp window-size
Syntax Description
Defaults
2144 bytes
Command Modes
Global configuration
Command History
Usage Guidelines
Do not use this command unless you clearly understand why you want to change the default value.
If your TCP window size is set to 1000 bytes, for example, you could have 1 packet of 1000 bytes or 2 packets of 500 bytes, and so on. However, there is also a limit on the number of packets allowed in the window. There can be a maximum of 5 packets if the connection has TTY; otherwise there can be 20 packets.
Examples
The following example sets the TCP window size to 1000 bytes:
ip tcp window-size 1000 ip unreachables
To enable the generation of ICMP Unreachable messages, use the ip unreachables interface configuration command. To disable this function, use the no form of this command.
ip unreachables
no ip unreachables
Syntax Description
This command has no arguments or keywords.
Defaults
Enabled
Command Modes
Interface configuration
Command History
Usage Guidelines
If the Cisco IOS software receives a nonbroadcast packet destined for itself that uses a protocol it does not recognize, it sends an ICMP Protocol Unreachable message to the source.
If the software receives a datagram that it cannot deliver to its ultimate destination because it knows of no route to the destination address, it replies to the originator of that datagram with an ICMP Host Unreachable message.
This command affects all kinds of ICMP unreachable messages.
Examples
The following example enables the generation of ICMP Unreachable messages, as appropriate, on an interface:
interface ethernet 0 ip unreachables permit (IP)
To set conditions for a named IP access list, use the permit access-list configuration command. To remove a condition from an access list, use the no form of this command.
permit {source [source-wildcard] | any} [log]
no permit {source [source-wildcard] | any}
permit protocol source source-wildcard destination destination-wildcard [precedence precedence] [tos tos] [log]
no permit protocol source source-wildcard destination destination-wildcard [precedence precedence] [tos tos] [log] [fragments]
ICMP
permit icmp source source-wildcard destination destination-wildcard [icmp-type [icmp-code] | icmp-message] [precedence precedence] [tos tos] [log] [fragments]
IGMP
permit igmp source source-wildcard destination destination-wildcard [igmp-type] [precedence precedence] [tos tos] [log] [fragments]
TCP
permit tcp source source-wildcard [operator port [port]] destination destination-wildcard [operator port [port]] [established] [precedence precedence] [tos tos] [log] [fragments]
UDP
permit udp source source-wildcard [operator port [port]] destination destination-wildcard [operator port [port]] [precedence precedence] [tos tos] [log] [fragments]
Syntax Description
Defaults
There are no specific conditions under which a packet passes the named access list.
Command Modes
Access-list configuration
Command History
Usage Guidelines
Use this command following the ip access-list command to define the conditions under which a packet passes the access list.
Access List Processing of Fragments
The behavior of access-list entries regarding the use or lack of the fragments keyword can be summarized as follows:
Be aware that you should not simply add the fragments keyword to every access list entry because the first fragment of the IP packet is considered a nonfragment and is treated independently of the subsequent fragments. An initial fragment will not match an access list permit or deny entry that contains the fragments keyword, the packet is compared to the next access list entry, and so on, until it is either permitted or denied by an access list entry that does not contain the fragments keyword. Therefore, you may need two access list entries for every deny entry. The first deny entry of the pair will not include the fragments keyword, and applies to the initial fragment. The second deny entry of the pair will include the fragments keyword and applies to the subsequent fragments. In the cases where there are multiple deny access list entries for the same host but with different Layer 4 ports, a single deny access-list entry with the fragments keyword for that host is all that needs to be added. Thus all the fragments of a packet are handled in the same manner by the access list.
Packet fragments of IP datagrams are considered individual packets and each counts individually as a packet in access list accounting and access list violation counts.
Note
The fragments keyword cannot solve all cases involving access lists and IP fragments.
Fragments and Policy Routing
Fragmentation and the fragment control feature affect policy routing if the policy routing is based on the match ip address command and the access list had entries that match on Layer 4 through 7 information. It is possible that noninitial fragments pass the access list and are policy routed, even if the first fragment was not policy routed or the reverse.
By using the fragments keyword in access list entries as described earlier, a better match between the action taken for initial and noninitial fragments can be made and it is more likely policy routing will occur as intended.
Examples
The following example sets conditions for a standard access list named Internetfilter:
ip access-list standard Internetfilter deny 192.5.34.0 0.0.0.255 permit 128.88.0.0 0.0.255.255 permit 36.0.0.0 0.255.255.255 ! (Note: all other access implicitly denied) Related Commands
show access-lists
To display the contents of current access lists, use the show access-lists privileged EXEC command.
show access-lists [access-list-number | name]
Syntax Description
Defaults
The system displays all access lists.
Command Modes
Privileged EXEC
Examples
The following is sample output from the show access-lists command when access list 101 is specified:
Router# show access-lists 101 Extended IP access list 101 permit tcp host 198.92.32.130 any established (4304 matches) permit udp host 198.92.32.130 any eq domain (129 matches) permit icmp host 198.92.32.130 any permit tcp host 198.92.32.130 host 171.69.2.141 gt 1023 permit tcp host 198.92.32.130 host 171.69.2.135 eq smtp (2 matches) permit tcp host 198.92.32.130 host 198.92.30.32 eq smtp permit tcp host 198.92.32.130 host 171.69.108.33 eq smtp permit udp host 198.92.32.130 host 171.68.225.190 eq syslog permit udp host 198.92.32.130 host 171.68.225.126 eq syslog deny ip 150.136.0.0 0.0.255.255 224.0.0.0 15.255.255.255 deny ip 171.68.0.0 0.1.255.255 224.0.0.0 15.255.255.255 (2 matches) deny ip 172.24.24.0 0.0.1.255 224.0.0.0 15.255.255.255 deny ip 192.82.152.0 0.0.0.255 224.0.0.0 15.255.255.255 deny ip 192.122.173.0 0.0.0.255 224.0.0.0 15.255.255.255 deny ip 192.122.174.0 0.0.0.255 224.0.0.0 15.255.255.255 deny ip 192.135.239.0 0.0.0.255 224.0.0.0 15.255.255.255 deny ip 192.135.240.0 0.0.7.255 224.0.0.0 15.255.255.255 deny ip 192.135.248.0 0.0.3.255 224.0.0.0 15.255.255.255 deny ip 192.150.42.0 0.0.0.255 224.0.0.0 15.255.255.255
An access list counter counts how many packets are allowed by each line of the access list. This number is displayed as the number of matches.
For information on how to configure access lists, refer to the "Configuring IP Services" chapter of the Network Protocols Configuration Guide, Part 1.
For information on how to configure dynamic access lists, refer to the "Traffic Filtering and Firewalls" chapter of the Security Configuration Guide.
Related Commands
show interface mac
To display MAC accounting information for interfaces configured for MAC accounting, use the show interface mac EXEC command.
show interface [type number] mac
Syntax Description
Command Modes
EXEC
Command History
Usage Guidelines
The show interface mac command displays information for all interfaces configured for MAC accounting. To display information for a single interface, use the show interface type number mac command.
For incoming packets on the interface, the accounting statistics are gathered before the CAR/DCAR feature is performed on the packet. For outgoing packets on the interface, the accounting statistics are gathered after output CAR, before output DCAR or DWRED or DWFQ feature is performed on the packet. Therefore, if a you are using DCAR or DWRED on the interface and packets are dropped, the dropped packets are still counted in the show interface mac command because the calculations are done prior to the features.
The maximum number of MAC addresses that can be stored for the input address is 512 and the maximum number of MAC address that can be stored for the output address is 512. After the maximum is reached, subsequent MAC addresses are ignored.
To clear the accounting statistics, use the clear counter EXEC command.To configure an interface for IP accounting based on the MAC address, use the ip accounting mac-address interface configuration command.
Examples
The following is sample output from the show interface mac command. This feature calculates the total packet and byte counts for the interface that receives (input) or sends (output) IP packets to or from a unique MAC address. It also records a timestamp for the last packet received or sent.
Router# show interface ethernet 0/1/1 mac Ethernet0/1/1 Input (511 free) 0007.f618.4449(228): 4 packets, 456 bytes, last: 2684ms ago Total: 4 packets, 456 bytes Output (511 free) 0007.f618.4449(228): 4 packets, 456 bytes, last: 2692ms ago Total: 4 packets, 456 bytes Related Commands
show interface precedence
To display precedence accounting information for interfaces configured for precedence accounting, use the show interface mac EXEC command.
show interface [type number] precedence
Syntax Description
Command Modes
EXEC
Command History
Usage Guidelines
The show interface precedence command displays information for all interfaces configured for IP precedence accounting. To display information for a single interface, use the show interface type number precedence command.
For incoming packets on the interface, the accounting statistics are gathered before input CAR/DCAR is performed on the packet. Therefore, if CAR/DCAR changes the precedence on the packet, it is counted based on the old precedence setting with the show interface precedence command.
For outgoing packets on the interface, the accounting statistics are gathered after output DCAR or DWRED or DWFQ feature is performed on the packet.
To clear the accounting statistics, use the clear counter EXEC command.
To configure an interface for IP accounting based on IP precedence, use the ip accounting precedence interface configuration command.
Examples
The following is sample output from the show interface precedence command. This feature calculates the total packet and byte counts for the interface that receives (input) or sends (output) IP packets and sorts the results based on IP precedence.
Router# show interface ethernet 0/1/1 precedence Ethernet0/1/1 Input Precedence 0: 4 packets, 456 bytes Output Precedence 0: 4 packets, 456 bytes Related Commands
show ip access-list
To display the contents of all current IP access lists, use the show ip access-list EXEC command.
show ip access-list [access-list-number | name]
Syntax Description
Defaults
Displays all standard and extended IP access lists.
Command Modes
EXEC
Command History
Usage Guidelines
The show ip access-list command provides output identical to the show access-lists command, except that it is IP-specific and allows you to specify a particular access list.
Examples
The following is sample output from the show ip access-list command when all are requested:
Router# show ip access-list Extended IP access list 101 deny udp any any eq ntp permit tcp any any permit udp any any eq tftp permit icmp any any permit udp any any eq domain
The following is sample output from the show ip access-list command when the name of a specific access list is requested:
Router# show ip access-list Internetfilter Extended IP access list Internetfilter permit tcp any 171.69.0.0 0.0.255.255 eq telnet deny tcp any any deny udp any 171.69.0.0 0.0.255.255 lt 1024 deny ip any any log show ip accounting
To display the active accounting or checkpointed database or to display access list violations, use the show ip accounting EXEC command.
show ip accounting [checkpoint] [output-packets | access-violations]
Syntax Description
Defaults
If neither the output-packets nor access-violations keyword is specified, show ip accounting displays information pertaining to packets that passed access control and were successfully routed.
Command Modes
EXEC
Command History
Usage Guidelines
If you do not specify any keywords, the show ip accounting command displays information about the active accounting database, and traffic coming from a remote site and transiting through a router.
To display IP access violations, you must give the access-violations keyword on the command. If you do not specify the keyword, the command defaults to displaying the number of packets that have passed access lists and were routed.
To use this command, you must first enable IP accounting on a per-interface basis.
Examples
The following is sample output from the show ip accounting command:
Router# show ip accounting Source Destination Packets Bytes 131.108.19.40 192.67.67.20 7 306 131.108.13.55 192.67.67.20 67 2749 131.108.2.50 192.12.33.51 17 1111 131.108.2.50 130.93.2.1 5 319 131.108.2.50 130.93.1.2 463 30991 131.108.19.40 130.93.2.1 4 262 131.108.19.40 130.93.1.2 28 2552 131.108.20.2 128.18.6.100 39 2184 131.108.13.55 130.93.1.2 35 3020 131.108.19.40 192.12.33.51 1986 95091 131.108.2.50 192.67.67.20 233 14908 131.108.13.28 192.67.67.53 390 24817 131.108.13.55 192.12.33.51 214669 9806659 131.108.13.111 128.18.6.23 27739 1126607 131.108.13.44 192.12.33.51 35412 1523980 192.31.7.21 130.93.1.2 11 824 131.108.13.28 192.12.33.2 21 1762 131.108.2.166 192.31.7.130 797 141054 131.108.3.11 192.67.67.53 4 246 192.31.7.21 192.12.33.51 15696 695635 192.31.7.24 192.67.67.20 21 916 131.108.13.111 128.18.10.1 16 1137 accounting threshold exceeded for 7 packets and 433 bytes
The following is sample output from the show ip accounting access-violations command. The output pertains to packets that failed access lists and were not routed:
Router# show ip accounting access-violations Source Destination Packets Bytes ACL 131.108.19.40 192.67.67.20 7 306 77 131.108.13.55 192.67.67.20 67 2749 185 131.108.2.50 192.12.33.51 17 1111 140 131.108.2.50 130.93.2.1 5 319 140 131.108.19.40 130.93.2.1 4 262 77 Accounting data age is 41
The following is sample output from the show ip accounting command. The output shows the original source and destination addresses that are separated by three routers:
Router3# show ip accounting Source Destination Packets Bytes 10.225.231.154 172.16.10.2 44 28160 10.76.97.34 172.16.10.2 44 28160 10.10.11.1 172.16.10.2 507 324480 10.10.10.1 172.16.10.2 507 318396 10.100.45.1 172.16.10.2 508 325120 10.98.32.5 172.16.10.2 44 28160 Accounting data age is 2
Table 11 describes the fields shown in the displays.
Related Commands
show ip drp
To display information about the DRP Server Agent for DistributedDirector, use the show ip drp EXEC command.
show ip drp
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Examples
The following is sample output from the show ip drp command:
Router# show ip drp Director Responder Protocol Agent is enabled 717 director requests, 712 successful lookups, 5 failures, 0 no route Authentication is enabled, using "test" key-chain
Table 12 describes the significant fields in the display.
Related Commands
show ip redirects
To display the address of a default gateway (router) and the address of hosts for which an ICMP Redirect messages has been received, use the show ip redirects EXEC command.
show ip redirects
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Usage Guidelines
This command displays the default router (gateway) as configured by the ip default-gateway command.
The ip redirects command enables the router to send ICMP Redirect messages.
Examples
The following is sample output from the show ip redirects command:
Router# show ip redirects Default gateway is 160.89.80.29 Host Gateway Last Use Total Uses Interface 131.108.1.111 160.89.80.240 0:00 9 Ethernet0 128.95.1.4 160.89.80.240 0:00 4 Ethernet0 Router# Related Commands
show ip sockets
To display IP socket information, use the show ip sockets command in privileged EXEC mode or user EXEC mode.
show ip sockets
Syntax Description
This command has no keywords or arguments.
Defaults
No default behavior or values.
Command Modes
Privileged EXEC
User EXEC Command History
Usage Guidelines
Use this command to verify that the socket being used is opening correctly. If there is a local and remote endpoint, a connection is established with the ports indicated.
Examples
The following is sample output from the show ip sockets command:
Router# show ip sockets Proto Remote Port Local Port In Out Stat TTY OutputIF 17 0.0.0.0 0 171.68.186.193 67 0 0 1 0 17 171.68.191.135 514 171.68.191.129 1811 0 0 0 0 17 172.16.135.20 514 171.68.191.1 4125 0 0 0 0 17 171.68.207.163 49 171.68.186.193 49 0 0 9 0 17 0.0.0.0 123 171.68.186.193 123 0 0 1 0 88 0.0.0.0 0 171.68.186.193 202 0 0 0 0 17 172.16.96.59 32856 171.68.191.1 161 0 0 1 0 17 --listen-- --any-- 496 0 0 1 0
Table 13 describes the significant fields shown in the display.
show ip tcp header-compression
To display statistics about TCP header compression, use the show ip tcp header-compression EXEC command.
show ip tcp header-compression
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Examples
The following is sample output from the show ip tcp header-compression command:
Router# show ip tcp header-compression TCP/IP header compression statistics: Interface Serial1: (passive, compressing) Rcvd: 4060 total, 2891 compressed, 0 errors 0 dropped, 1 buffer copies, 0 buffer failures Sent: 4284 total, 3224 compressed, 105295 bytes saved, 661973 bytes sent 1.15 efficiency improvement factor Connect: 16 slots, 1543 long searches, 2 misses, 99% hit ratio Five minute miss rate 0 misses/sec, 0 max misses/sec
Table 14 describes significant fields shown in the display.
Related Commands
show ip traffic
To display statistics about IP traffic, use the show ip traffic EXEC command.
show ip traffic
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Examples
The following is sample output from the show ip traffic command:
Router# show ip traffic IP statistics: Rcvd: 98 total, 98 local destination 0 format errors, 0 checksum errors, 0 bad hop count 0 unknown protocol, 0 not a gateway 0 security failures, 0 bad options Frags: 0 reassembled, 0 timeouts, 0 too big 0 fragmented, 0 couldn't fragment Bcast: 38 received, 52 sent Sent: 44 generated, 0 forwarded 0 encapsulation failed, 0 no route ICMP statistics: Rcvd: 0 format errors, 0 checksum errors, 0 redirects, 0 unreachable 0 echo, 0 echo reply, 0 mask requests, 0 mask replies, 0 quench 0 parameter, 0 timestamp, 0 info request, 0 other Sent: 0 redirects, 3 unreachable, 0 echo, 0 echo reply 0 mask requests, 0 mask replies, 0 quench, 0 timestamp 0 info reply, 0 time exceeded, 0 parameter problem UDP statistics: Rcvd: 56 total, 0 checksum errors, 55 no port Sent: 18 total, 0 forwarded broadcasts TCP statistics: Rcvd: 0 total, 0 checksum errors, 0 no port Sent: 0 total EGP statistics: Rcvd: 0 total, 0 format errors, 0 checksum errors, 0 no listener Sent: 0 total IGRP statistics: Rcvd: 73 total, 0 checksum errors Sent: 26 total HELLO statistics: Rcvd: 0 total, 0 checksum errors Sent: 0 total ARP statistics: Rcvd: 20 requests, 17 replies, 0 reverse, 0 other Sent: 0 requests, 9 replies (0 proxy), 0 reverse Probe statistics: Rcvd: 6 address requests, 0 address replies 0 proxy name requests, 0 other Sent: 0 address requests, 4 address replies (0 proxy) 0 proxy name replies
Table 15 describes significant fields shown in the display.
show standby
To display Hot Standby Router Protocol (HSRP) information, use the show standby EXEC command.
show standby [type number [group]] [brief]
Syntax Description
Command Modes
EXEC
Command History
Usage Guidelines
If you want to specify a group, you must also specify an interface type and number.
Examples
The following is sample output from the show standby command:
Router# show standby Ethernet0 - Group 0 Local state is Active, priority 100, may preempt Hellotime 3 holdtime 10 Next hello sent in 0:00:00 Hot standby IP address is 198.92.72.29 configured Active router is local Standby router is 198.92.72.21 expires in 0:00:07 Tracking interface states for 2 interfaces, 2 up: Up Ethernet0 Up Serial0
The following is sample output from the show standby command with a specific interface and the brief keyword:
Router# show standby ethernet0 brief Interface Grp Prio P State Active addr Standby addr Group addr Et0 0 100 Standby 171.69.232.33 local 172.19.48.254
Table 16 describes the fields in the display.
Related Commands
show tcp statistics
To display TCP statistics, use the show tcp statistics EXEC command.
show tcp statistics
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Examples
The following is sample output from the show tcp statistics command:
Router# show tcp statistics Rcvd: 210 Total, 0 no port 0 checksum error, 0 bad offset, 0 too short 132 packets (26640 bytes) in sequence 5 dup packets (502 bytes) 0 partially dup packets (0 bytes) 0 out-of-order packets (0 bytes) 0 packets (0 bytes) with data after window 0 packets after close 0 window probe packets, 0 window update packets 0 dup ack packets, 0 ack packets with unsend data 69 ack packets (3044 bytes) Sent: 175 Total, 0 urgent packets 16 control packets (including 1 retransmitted) 69 data packets (3029 bytes) 0 data packets (0 bytes) retransmitted 73 ack only packets (49 delayed) 0 window probe packets, 17 window update packets 7 Connections initiated, 1 connections accepted, 8 connections established 8 Connections closed (including 0 dropped, 0 embryonic dropped) 1 Total rxmt timeout, 0 connections dropped in rxmt timeout 0 Keepalive timeout, 0 keepalive probe, 0 Connections dropped in keepalive
Table 17 describes significant fields shown in the display.
Related Commands
standby authentication
To configure an authentication string for the Hot Standby Router Protocol (HSRP), use the standby authentication interface configuration command. To delete an authentication string, use the no form of this command.
standby [group-number] authentication string
no standby [group-number] authentication string
Syntax Description
Defaults
group-number: 0
string: cisco Command Modes
Interface configuration
Command History
Usage Guidelines
The authentication string is transmitted unencrypted in all HSRP messages. The same authentication string must be configured on all routers and access servers on a cable to ensure interoperation. Authentication mismatch prevents a device from learning the designated Hot Standby IP address and the Hot Standby timer values from other routers configured with HSRP. Authentication mismatch does not prevent protocol events such as one router taking over as the designated router.
When group number 0 is used, no group number is written to NVRAM, providing backward compatibility.
Examples
The following example configures "word" as the authentication string required to allow Hot Standby routers in group 1 to interoperate:
interface ethernet 0 standby 1 authentication word standby ip
To activate the Hot Standby Router Protocol (HSRP), use the standby ip interface configuration command. To disable HSRP, use the no form of this command.
standby [group-number] ip [ip-address [secondary]]
no standby [group-number] ip [ip-address]
Syntax Description
Defaults
group-number: 0
HSRP is disabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
The standby ip command activates HSRP on the configured interface. If an IP address is specified, that address is used as the designated address for the Hot Standby group. If no IP address is specified, the designated address is learned through the standby function. For HSRP to elect a designated router, at least one router on the cable must have been configured with, or learned, the designated address. Configuring the designated address on the active router always overrides a designated address that is currently in use.
When the standby ip command is enabled on an interface, the handling of proxy ARP requests is changed (unless proxy ARP was disabled). If the interface's Hot Standby state is active, proxy ARP requests are answered using the Hot Standby group's MAC address. If the interface is in a different state, proxy ARP responses are suppressed.
When group number 0 is used, no group number is written to NVRAM, providing backward compatibility.
Examples
The following example activates HSRP for group 1 on Ethernet interface 0. The IP address used by the Hot Standby group will be learned using HSRP.
interface ethernet 0 standby 1 ip
In the following example, all three virtual IP addresses appear in the ARP table using the same (single) virtual MAC address. All three virtual IP addresses are using the same HSRP group (group 0).
ip address 1.1.1.1. 255.255.255.0 ip address 1.2.2.2. 255.255.255.0 secondary ip address 1.3.3.3. 255.255.255.0 secondary ip address 1.4.4.4. 255.255.255.0 secondary standby ip 1.1.1.254 standby ip 1.2.2.254 secondary standby ip 1.3.3.254 secondary standby mac-address
To specify a virtual MAC address for Hot Standby Router Protocol (HSRP), use the standby mac-address interface configuration command. To revert to the standard virtual MAC address (0000.0C07.ACxy), use the no form of this command.
standby [group-number] mac-address macaddress
no standby [group-number] mac-address
Syntax Description
Defaults
If this command is not configured, and the standby use-bia command is not configured, the standard virtual MAC address is used: 0000.0C07.ACxy, where xy is the group number in hexadecimal. This address is specified in RFC 2281, Cisco Hot Standby Router Protocol (HSRP).
Command Modes
Interface configuration
Command History
Usage Guidelines
This command can not be used on a Token Ring Interface.
HSRP is used to help endstations locate the first hop gateway for IP routing. The endstations are configured with a default gateway. However, HSRP can provide first-hop redundancy for other protocols. Some protocols, such as APPN, use the MAC address to identify the first hop for routing purposes. In this case, it is often necessary to be able to specify the virtual MAC address; the virtual IP address is unimportant for these protocols. Use the standby mac-address command to specify the virtual MAC address.
The MAC address specified is used as the virtual MAC address when the router is active.
This command is intended for certain APPN configurations. The parallel terms are as follows:
APPN IP
end node host network node router or gateway
In an APPN network, an end node is typically configured with the MAC address of the adjacent network node. Use the standby mac-address command in the routers to set the virtual MAC address to the value used in the end nodes.
Examples
If the end nodes are configured to use 4000.1000.1060 as the MAC address of the network node, the command to configure HSRP group 1 with the virtual MAC address is as follows:
standby 1 mac-address 4000.1000.1060 Related Commands
standby mac-refresh
To change the interval at which packets are sent to refresh the MAC cache when Hot Standby Router Protocol (HSRP) is running over FDDI, use the standby mac-refresh interface configuration command. To restore the default value, use the no form of this command.
standby mac-refresh seconds
no standby mac-refresh
Syntax Description
Defaults
10 seconds
Command Modes
Interface configuration
Command History
Usage Guidelines
This command applies to HSRP running over FDDI only. Packets are sent every 10 seconds to refresh the MAC cache on learning bridges or switches. By default, the MAC cache entries age out in 300 seconds (5 minutes).
All other routers participating in HSRP on the FDDI ring receive the refresh packets, although the packets are intended only for the learning bridge or switch. Use this command to change the interval. Set the interval to 0 if you want to prevent refresh packets (if you have FDDI but do not have a learning bridge or switch).
Examples
The following example changes the MAC refresh interval to 100 seconds. Therefore, a learning bridge would have to miss three packets before the entry ages out.
standby mac-refresh 100 standby priority, standby preempt
To configure Hot Standby Router Protocol (HSRP) priority, preemption, and preemption delay, use the standby interface configuration command. To restore the default values, use the no form of this command.
standby [group-number] priority priority [preempt [delay delay]]
standby [group-number] [priority priority] preempt [delay delay]
no standby [group-number] priority priority [preempt [delay delay]]
no standby [group-number] [priority priority] preempt [delay delay]
Syntax Description
Defaults
group-number: 0
priority: 100
delay: 0 seconds; if the router wants to preempt, it will do so immediately.
Command Modes
Interface configuration
Command History
Usage Guidelines
When using this command, you must specify at least one keyword (priority or preempt), or you can specify both.
When group number 0 is used, no group number is written to NVRAM, providing backward compatibility.
The assigned priority is used to help select the active and standby routers. Assuming preemption is enabled, the router with the highest priority becomes the designated active router. In case of ties, the primary IP addresses are compared, and the higher IP address has priority.
Note that the device's priority can change dynamically if an interface is configured with the standby track command and another interface on the router goes down.
When a router first comes up, it does not have a complete routing table. If it is configured to preempt, it will become the active router, yet it is unable to provide adequate routing services. This problem is solved by configuring a delay before the preempting router actually preempts the currently active router.
Examples
In the following example, the router has a priority of 120 (higher than the default value) and will wait for 300 seconds (5 minutes) before attempting to become the active router:
interface ethernet 0 standby ip 172.19.108.254 standby priority 120 preempt delay 300 Related Commands
standby timers
To configure the time between hellos and the time before other routers declare the active Hot Standby or standby router to be down, use the standby timers interface configuration command. To restore the timers to their default values, use the no form of this command.
standby [group-number] timers [msec] hellotime [msec] holdtime
no standby [group-number] timers [msec] hellotime [msec] holdtime
Syntax Description
Defaults
group-number: 0
hellotime: 3 seconds holdtime: 10 seconds Command Modes
Interface configuration
Command History
Usage Guidelines
The standby timers command configures the time between standby hellos and the time before other routers declare the active or standby router to be down. Routers or access servers on which timer values are not configured can learn timer values from the active or standby router. The timers configured on the active router always override any other timer settings. All routers in a Hot Standby group should use the same timer values. Normally, holdtime is greater than or equal to 3 times the value of hellotime, (holdtime > 3 * hellotime).
The value of the standby timer will not be learned through HSRP hellos if it is less than 1 second.
When group number 0 is used, no group number is written to NVRAM, providing backward compatibility.
Examples
The following example sets, for group number 1 on Ethernet interface 0, the time between hello packets to 5 seconds, and the time after which a router is considered to be down to 15 seconds:
interface ethernet 0 standby 1 ip standby 1 timers 5 15
The following example sets, for the Hot Router interface located at 172.19.10.1 on Ethernet interface 0, the time between hello packets to 300 milliseconds, and the time after which a router is considered to be down to 900 milliseconds.
interface ethernet 0 standby ip 172.19.10.1 standby timers msec 300 msec 900 standby track
To configure an interface so that the Hot Standby priority changes based on the availability of other interfaces, use the standby track interface configuration command. To remove the tracking, use the no form of this command.
standby [group-number] track type number [interface-priority]
no standby [group-number] track type number [interface-priority]
Syntax Description
Defaults
group-number: 0
interface-priority: 10
Command Modes
Interface configuration
Command History
Usage Guidelines
This command ties the router's Hot Standby priority to the availability of its interfaces. It is useful for tracking interfaces that are not configured for the Hot Standby Router Protocol.
When a tracked interface goes down, the Hot Standby priority decreases by 10. If an interface is not tracked, its state changes do not affect the Hot Standby priority. For each interface configured for Hot Standby, you can configure a separate list of interfaces to be tracked.
The optional argument interface-priority specifies how much to decrement the Hot Standby priority by when a tracked interface goes down. When the tracked interface comes back up, the priority is incremented by the same amount.
When multiple tracked interfaces are down and interface-priority values have been configured, these configured priority decrements are cumulative. If tracked interfaces are down, but none of them were configured with priority decrements, the default decrement is 10 and it is noncumulative.
When group number 0 is used, no group number is written to NVRAM, providing backward compatibility.
Examples
In the following example, Ethernet interface 1 tracks Ethernet interface 0 and serial interface 0. If one or both of these two interfaces go down, the Hot Standby priority of the router decreases by 10. Because the default Hot Standby priority is 100, the priority becomes 90 when one or both of the tracked interfaces go down.
interface ethernet 1 ip address 198.92.72.37 255.255.255.240 no ip redirects standby track ethernet 0 standby track serial 0 standby preempt standby ip 198.92.72.46 Related Commands
standby use-bia
To configure Hot Standby Router Protocol (HSRP) to use the interface's burned-in address as its virtual MAC address, instead of the preassigned MAC address (on Ethernet and FDDI) or the functional address (on Token Ring), use the standby use-bia interface configuration command. To restore the default virtual MAC address, use the no form of this command.
standby use-bia
no standby use-bia
Syntax Description
This command has no arguments or keywords.
Defaults
HSRP uses the preassigned MAC address on Ethernet and FDDI, or the functional address on Token Ring.
Command Modes
Interface configuration
Command History
Usage Guidelines
For an interface with this command configured, only one standby group can be configured. Multiple groups need to be removed before this command is configured. Hosts on the interface need to have a default gateway configured. It is recommended you set the no ip proxy-arp command on the interface. It is desirable to configure the standby use-bia command on a Token Ring interface if there are devices that reject ARP replies with source hardware addresses set to a functional address.
When HSRP runs on a multiple-ring, source-routed bridging environment and the HRSP routers reside on different rings, configuring the standby use-bia command can prevent RIF confusion.
Examples
In the following example, the burned-in address of Token Ring interface 4/0 will be the virtual MAC address mapped to the virtual IP address:
interface token4/0 standby use-bia transmit-interface
To assign a transmit interface to a receive-only interface, use the transmit-interface interface configuration command. To return to normal duplex Ethernet interfaces, use the no form of this command.
transmit-interface type number
no transmit-interface
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
Receive-only interfaces are used commonly with microwave Ethernet links.
Examples
The following example specifies Ethernet interface 0 as a simplex Ethernet interface:
interface ethernet 1 ip address 128.9.1.2 transmit-interface ethernet 0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Wednesday, October 16, 2013
Cisco IP Services Commands
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