Table of Contents

Command Descriptions

address-violation
autobaud
back-pressure
banner motd
bridge (forwarding-time)
bridge-group
bridge-group (allow-overlap)
bridge-group (enable)
bridge (hello-time)
bridge (max-age)
bridge (priority)
cdp (advertise-v2)
cdp (enable)
cdp (holdtime)
cdp (timer)
cgmp
cgmp (hold-time)
cgmp (leave-processing)
cgmp (remove)
cgmp (reserved)
clear (cgmp)
clear (dns-cache)
clear (counters)
clear (mac-address-table)
clear (uplink-fast statistics)
clear (vtp statistics)
cluster
configure
copy (nvram tFTP)
copy (tftp)
copy (xmodem)
databits
delete (nvram)
delete (vtp)
description
disable
duplex
ecc
enable
enable (passWord)
enable (secret)
enable (use-tacacs)
end
exit
fddi (authorization)
fddi (auth-string)
fddi (notify-timer)
fddi (novell-snap-translation)
fddi (unmatched-snap-translation)
hostname
interface
ip (address)
ip (default-gateway)
ip (domain-name)
ip (http port)
ip (http server)
ip (mgmt-vlan)
ip (name-server)
line console
login (tacacs)
mac-address-table (aging-time)
mac-address-table (permanent)
mac-address-table (restricted static)
menu
modem (dialin)
modem (init-string)
monitor-port
monitor-port (monitored)
monitor-port (port)
multicast-store-and-forward
network-port
pagp-port-priority
parity
password-thresh
ping
port (block)
port-channel (mode)
port-channel (preserve-order)
port-channel (template-port)
port secure
port secure (clear)
reload
reload (in)
rip
service (config)
session
show (bridge-group)
show cdp (interface)
show cdp (neighbors)
show (cgmp)
show cluster
show (history)
show (interfaces)

Command Descriptions
This chapter is a command-by-command description of the firmware version 9.00 CLI commands for the Catalyst 1900 series and Catalyst 2820 series switches.
address-violation
Use the address-violation global configuration command to specify the action for a port address violation. Use the no address-violation command to set the switch to its default value (suspend).
address-violation {suspend disable ignore}

no address-violation
Syntax Description
suspend Suspend port on address violation. A suspended port is temporarily disabled until a certain number of frames with the proper address is received.
disable Disable port on address violation.
ignore Ignore address violation.

Default
The port is suspended on address violation.
Command Mode
Global configuration
Usage Guidelines
An address violation occurs when a secured port receives a source address that has been assigned to another secured port or when a port tries to learn an address that exceeds the address-table size limit.
Example
This command causes the switch to disable the port on address violation.
hostname(config)# address-violation disable
Related Commands
port secure
show (port system)
autobaud
Use the autobaud line-configuration command to enable remote baud-rate matching. Use the no autobaud command to disable remote baud-rate matching.
autobaud
no autobaud
Syntax Description
This command has no arguments or keywords.
Default
Remote baud-rate matching is enabled.
Command Mode
Line configuration
Example
This example shows how to enable remote baud-rate matching.
hostname(config-line)# autobaud
Related Commands
databits
line console
modem (dialin)
parity
show (line)
show (terminal)
speed
stopbits
terminal
back-pressure
Use the back-pressure global configuration command to enable back pressure. Use the no back-pressure command to disable back pressure.
back-pressure
no back-pressure
Syntax Description
This command has no arguments or keywords.
Default
Back pressure is disabled.
Command Mode
Global configuration
Usage Guidelines
When the back-pressure command is enabled, the switch forces a collision when there is no buffer to receive frames. This collision causes the transmitter to retransmit dropped frames immediately, increasing performance. The command is valid only for a 10BaseT port operating in half-duplex mode.
Example
This example shows how to enable back pressure.
hostname(config)# back-pressure
Related Commands
configure
duplex
show (interfaces)
show (port system)
banner motd
Use the banner motd global configuration command to set the message-of-the-day (MOTD) banner. Use the no banner motd command to remove the banner.
banner [motd] d message d
no banner [motd]
Syntax
motd Optional command acronym for "message of the day."
d Delimiting character---a pound sign (#), for example. Do not use the delimiting character in the banner message.
message Message text up to 400 characters or 20 lines.

Default
No MOTD is set.
Command Mode
Global configuration
Usage Guidelines

When configuring a multiline banner, the multiline help prompt displays after you enter the first line of the banner:
Enter TEXT message. End with the character c

where c is the delimiting character you choose.
When a MOTD banner is set, it displays at the login screen to the serial port console and all telnet connections (except the rcommand connections from a command switch). The maximum size of the banner is 400 characters or 20 lines, whichever is reached first.
Examples
This example sets the MOTD banner to Empowering the Internet Generation.
hostname(config)# banner motd # Empowering the Internet Generation #

This example shows how to set the MOTD banner message with line feeds.
hostname(config)# banner #

Enter TEXT message. End with the character #.
Line 1 is now up.
Line 2 is still down.
#

This example shows how to remove the MOTD banner.
hostname(config)# no banner motd
Related Commands
None
bridge (forwarding-time)
Use the bridge forwarding-time global configuration command to set the Spanning-Tree Protocol (STP) forward-delay time for a particular bridge group. Use the no bridge forwarding-time command to reset the forward-delay time to its default value.
bridge bridge-group forwarding-time time
no bridge bridge-group forwarding-time
Syntax Description
bridge-group Number from 1 to 4.
time Number from 4 to 30 seconds.

Default
The default is 15 seconds.
Command Mode
Global configuration
Usage Guidelines
This command is available only when bridge groups are enabled.
Example
The following example shows how to set the forward-delay time to 10 seconds for bridge-group 1.
hostname(config)# bridge 1 forwarding-time 10
Related Commands
bridge (hello-time)
bridge (max-age)
bridge (priority)
bridge-group (allow-overlap)
bridge-group (enable)
show (bridge-group)
show (spantree)
spantree
bridge-group
Use the bridge-group interface configuration command to modify the assignments of ports to bridge groups. Use the no bridge-group command to remove ports from a bridge group.
bridge-group bridge-group
no bridge-group bridge-group
Syntax Description
bridge-group Number from 1 to 4.