Cisco Catalyst 2960-X Installation manual

Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS
Release 15.0(2)EX
First Published: July 10, 2013
Americas Headquarters
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
USA
http://www.cisco.com
Tel: [phone]
800 553-NETS (6387)
Fax: [phone]
Text Part Number: OL-29043 -01

THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT NOTICE. ALL STATEMENTS,
INFORMATION, AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED. USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF ANY PRODUCTS.
THE SOFTWARE LICENSE AND LIMITED WARRANTY FOR THE ACCOMPANYING PRODUCT ARE SET FORTH IN THE INFORMATION PACKET THAT SHIPPED WITH
THE PRODUCT AND ARE INCORPORATED HEREIN BY THIS REFERENCE. IF YOU ARE UNABLE TO LOCATE THE SOFTWARE LICENSE OR LIMITED WARRANTY,
CONTACT YOUR CISCO REPRESENTATIVE FOR A COPY.
The Cisco implementation of TCP header compression is an adaptation of a program developed by the University of California, Berkeley (UCB) as part of UCB's public domain version
of the UNIX operating system. All rights reserved. Copyright ©1981, Regents of the University of California.
NOTWITHSTANDING ANY OTHER WARRANTY HEREIN, ALL DOCUMENT FILES AND SOFTWARE OF THESE SUPPLIERS ARE PROVIDED “AS IS" WITH ALL FAULTS.
CISCO AND THE ABOVE-NAMED SUPPLIERS DISCLAIM ALL WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, THOSE OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OR ARISING FROM A COURSE OF DEALING, USAGE, OR TRADE PRACTICE.
IN NO EVENT SHALL CISCO OR ITS SUPPLIERS BE LIABLE FOR ANY INDIRECT, SPECIAL, CONSEQUENTIAL, OR INCIDENTAL DAMAGES, INCLUDING, WITHOUT
LIMITATION, LOST PROFITS OR LOSS OR DAMAGE TO DATA ARISING OUT OF THE USE OR INABILITY TO USE THIS MANUAL, EVEN IF CISCO OR ITS SUPPLIERS
HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network
topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional
and coincidental.
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: http://
www.cisco.com/go/trademarks. Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership
relationship between Cisco and any other company. (1110R)
©2013 Cisco Systems, Inc. All rights reserved.

CONTENTS
CHAPTER 1 Preface 1
Document Conventions 1
Related Documentation 3
Obtaining Documentation and Submitting a Service Request 3
CHAPTER 2 Using the Command-Line Interface 5
Information About Using the Command-Line Interface 5
Command Modes 5
Using the Help System 7
Understanding Abbreviated Commands 8
No and default Forms of Commands 8
CLI Error Messages 8
Configuration Logging 9
How to Use the CLI to Configure Features 9
Configuring the Command History 9
Changing the Command History Buffer Size 10
Recalling Commands 10
Disabling the Command History Feature 11
Enabling and Disabling Editing Features 11
Editing Commands through Keystrokes 13
Editing Command Lines That Wrap 14
Searching and Filtering Output of show and more Commands 15
Accessing the CLI through a Console Connection or through Telnet 16
CHAPTER 3 Layer 2 Commands 17
channel-group 20
channel-protocol 23
clear lacp 25
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 iii

clear pagp 26
clear spanning-tree counters 27
clear spanning-tree detected-protocols 28
debug etherchannel 29
debug lacp 31
debug pagp 32
debug platform etherchannel 34
debug platform pm 35
debug spanning-tree 38
debug platform udld 40
interface port-channel 41
lacp port-priority 43
lacp system-priority 45
link state group 47
link state track 48
pagp learn-method 49
pagp port-priority 51
pagp timer 53
port-channel load-balance 54
show etherchannel 55
show lacp 58
show link state group 63
show pagp 64
show platform backup interface 66
show platform etherchannel 67
show platform pm 68
show platform spanning-tree 70
show spanning-tree 71
show udld 74
spanning-tree backbonefast 77
spanning-tree bpdufilter 78
spanning-tree bpduguard 80
spanning-tree cost 81
spanning-tree etherchannel guard misconfig 83
spanning-tree extend system-id 84
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
iv OL-29043 -01
Contents

spanning-tree guard 86
spanning-tree link-type 88
spanning-tree loopguard default 89
spanning-tree mode 90
spanning-tree mst configuration 92
spanning-tree mst cost 94
spanning-tree mst forward-time 95
spanning-tree mst hello-time 96
spanning-tree mst max-age 97
spanning-tree mst max-hops 98
spanning-tree mst port-priority 99
spanning-tree mst pre-standard 100
spanning-tree mst priority 101
spanning-tree mst root 102
spanning-tree pathcost method 104
spanning-tree port-priority 105
spanning-tree portfast (global configuration) 106
spanning-tree portfast (interface configuration) 108
spanning-tree transmit hold-count 110
spanning-tree uplinkfast 111
spanning-tree vlan 113
switchport access vlan 115
switchport mode 116
switchport nonegotiate 119
udld 121
udld port 123
udld reset 125
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 v
Contents

Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
vi OL-29043 -01
Contents

Preface
This preface contains the following topics:
•Document Conventions, page 1
•Related Documentation, page 3
•Obtaining Documentation and Submitting a Service Request, page 3
Document Conventions
This document uses the following conventions:
DescriptionConvention
Both the ^symbol and Ctrl represent the Control (Ctrl) key on a keyboard.
For example, the key combination ^D or Ctrl-D means that you hold
down the Control key while you press the D key. (Keys are indicated in
capital letters but are not case sensitive.)
^ or Ctrl
Commands and keywords and user-entered text appear in bold font.bold font
Document titles, new or emphasized terms, and arguments for which you
supply values are in italic font.
Italic font
Terminal sessions and information the system displays appear in courier
font.
Courier font
Bold Courier font indicates text that the user must enter.Bold Courier font
Elements in square brackets are optional.[x]
An ellipsis (three consecutive nonbolded periods without spaces) after
a syntax element indicates that the element can be repeated.
...
A vertical line, called a pipe, indicates a choice within a set of keywords
or arguments.
|
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 1

DescriptionConvention
Optional alternative keywords are grouped in brackets and separated by
vertical bars.
[x | y]
Required alternative keywords are grouped in braces and separated by
vertical bars.
{x | y}
Nested set of square brackets or braces indicate optional or required
choices within optional or required elements. Braces and a vertical bar
within square brackets indicate a required choice within an optional
element.
[x {y | z}]
A nonquoted set of characters. Do not use quotation marks around the
string or the string will include the quotation marks.
string
Nonprinting characters such as passwords are in angle brackets.< >
Default responses to system prompts are in square brackets.[ ]
An exclamation point (!) or a pound sign (#) at the beginning of a line
of code indicates a comment line.
!, #
Reader Alert Conventions
This document uses the following conventions for reader alerts:
Means reader take note. Notes contain helpful suggestions or references to material not covered in the
manual.
Note
Means the following information will help you solve a problem.
Tip
Means reader be careful. In this situation, you might do something that could result in equipment damage
or loss of data.
Caution
Means the described action saves time. You can save time by performing the action described in the
paragraph.
Timesaver
Means reader be warned. In this situation, you might perform an action that could result in bodily
injury.
Warning
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
2OL-29043 -01
Preface
Document Conventions

Related Documentation
Before installing or upgrading the switch, refer to the switch release notes.Note
•Catalyst 2960-X Switch documentation, located at:
http://www.cisco.com/go/cat2960x_docs
•Cisco SFP and SFP+ modules documentation, including compatibility matrixes, located at:
http://www.cisco.com/en/US/products/hw/modules/ps5455/tsd_products_support_series_home.html
•Cisco Validated Designs documents, located at:
http://www.cisco.com/go/designzone
Obtaining Documentation and Submitting a Service Request
For information on obtaining documentation, submitting a service request, and gathering additional information,
see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco
technical documentation, at:
http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html
Subscribe to the What's New in Cisco Product Documentation as a Really Simple Syndication (RSS) feed
and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free
service and Cisco currently supports RSS version 2.0.
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 3
Preface
Related Documentation

Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
4OL-29043 -01
Preface
Obtaining Documentation and Submitting a Service Request

Using the Command-Line Interface
This chapter contains the following topics:
•Information About Using the Command-Line Interface, page 5
•How to Use the CLI to Configure Features, page 9
Information About Using the Command-Line Interface
This section describes the Cisco IOS command-line interface (CLI) and how to use it to configure your switch.
Command Modes
The Cisco IOS user interface is divided into many different modes. The commands available to you depend
on which mode you are currently in. Enter a question mark (?) at the system prompt to obtain a list of commands
available for each command mode.
You can start a CLI session through a console connection, through Telnet, a SSH, or by using the browser.
When you start a session, you begin in user mode, often called user EXEC mode. Only a limited subset of
the commands are available in user EXEC mode. For example, most of the user EXEC commands are one-time
commands, such as show commands, which show the current configuration status, and clear commands,
which clear counters or interfaces. The user EXEC commands are not saved when the switch reboots.
To have access to all commands, you must enter privileged EXEC mode. Normally, you must enter a password
to enter privileged EXEC mode. From this mode, you can enter any privileged EXEC command or enter
global configuration mode.
Using the configuration modes (global, interface, and line), you can make changes to the running configuration.
If you save the configuration, these commands are stored and used when the switch reboots. To access the
various configuration modes, you must start at global configuration mode. From global configuration mode,
you can enter interface configuration mode and line configuration mode.
This table describes the main command modes, how to access each one, the prompt you see in that mode, and
how to exit the mode.
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 5

Table 1: Command Mode Summary
About This ModeExit MethodPromptAccess MethodMode
Use this mode to
•Change
terminal
settings.
•Perform basic
tests.
•Display
system
information.
Enter logout or
quit.
Switch>
Begin a session
using Telnet, SSH,
or console.
User EXEC
Use this mode to
verify commands
that you have
entered. Use a
password to protect
access to this mode.
Enter disable to
exit.
Switch#
While in user EXEC
mode, enter the
enable command.
Privileged EXEC
Use this mode to
configure
parameters that
apply to the entire
switch.
To exit to privileged
EXEC mode, enter
exit or end, or press
Ctrl-Z.
Switch(config)#
While in privileged
EXEC mode, enter
the configure
command.
Global
configuration
Use this mode to
configure VLAN
parameters. When
VTP mode is
transparent, you can
create
extended-range
VLANs (VLAN IDs
greater than 1005)
and save
configurations in the
switch startup
configuration file.
To exit to global
configuration mode,
enter the exit
command.
To return to
privileged EXEC
mode, press Ctrl-Z
or enter end.
Switch(config-vlan)#
While in global
configuration mode,
enter the vlan
vlan-id command.
VLAN
configuration
Use this mode to
configure
parameters for the
Ethernet ports.
To exit to global
configuration mode,
enter exit.
To return to
privileged EXEC
mode, press Ctrl-Z
or enter end.
Switch(config-if)#
While in global
configuration mode,
enter the interface
command (with a
specific interface).
Interface
configuration
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
6OL-29043 -01
Using the Command-Line Interface
Command Modes

About This ModeExit MethodPromptAccess MethodMode
Line configuration Use this mode to
configure
parameters for the
terminal line.
To exit to global
configuration mode,
enter exit.
To return to
privileged EXEC
mode, press Ctrl-Z
or enter end.
Switch(config-line)#
While in global
configuration mode,
specify a line with
the line vty or line
console command.
Using the Help System
You can enter a question mark (?) at the system prompt to display a list of commands available for each
command mode. You can also obtain a list of associated keywords and arguments for any command.
SUMMARY STEPS
1. help
2. abbreviated-command-entry ?
3. abbreviated-command-entry <Tab>
4. ?
5. command ?
6. command keyword ?
DETAILED STEPS
PurposeCommand or Action
Obtains a brief description of the help system in any
command mode.
help
Example:
Switch# help
Step 1
Obtains a list of commands that begin with a particular
character string.
abbreviated-command-entry ?
Example:
Switch# di?
dir disable disconnect
Step 2
Completes a partial command name.
abbreviated-command-entry <Tab>
Example:
Switch# sh conf<tab>
Switch# show configuration
Step 3
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 7
Using the Command-Line Interface
Using the Help System

PurposeCommand or Action
Lists all commands available for a particular command
mode.
?
Example:
Switch> ?
Step 4
Lists the associated keywords for a command.
command ?
Example:
Switch> show ?
Step 5
Lists the associated arguments for a keyword.
command keyword ?
Example:
Switch(config)# cdp holdtime ?
<10-255> Length of time (in sec) that receiver
Step 6
must keep this packet
Understanding Abbreviated Commands
You need to enter only enough characters for the switch to recognize the command as unique.
This example shows how to enter the show configuration privileged EXEC command in an abbreviated form:
Switch# show conf
No and default Forms of Commands
Almost every configuration command also has a no form. In general, use the no form to disable a feature or
function or reverse the action of a command. For example, the no shutdown interface configuration command
reverses the shutdown of an interface. Use the command without the keyword no to reenable a disabled feature
or to enable a feature that is disabled by default.
Configuration commands can also have a default form. The default form of a command returns the command
setting to its default. Most commands are disabled by default, so the default form is the same as the no form.
However, some commands are enabled by default and have variables set to certain default values. In these
cases, the default command enables the command and sets variables to their default values.
CLI Error Messages
This table lists some error messages that you might encounter while using the CLI to configure your switch.
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
8OL-29043 -01
Using the Command-Line Interface
Understanding Abbreviated Commands

Table 2: Common CLI Error Messages
How to Get HelpMeaningError Message
Reenter the command followed by
a question mark (?) with a space
between the command and the
question mark.
The possible keywords that you can
enter with the command appear.
You did not enter enough
characters for your switch to
recognize the command.
% Ambiguous command: "show
con"
Reenter the command followed by
a question mark (?) with a space
between the command and the
question mark.
The possible keywords that you can
enter with the command appear.
You did not enter all the keywords
or values required by this
command.
% Incomplete command.
Enter a question mark (?) to display
all the commands that are available
in this command mode.
The possible keywords that you can
enter with the command appear.
You entered the command
incorrectly. The caret (^) marks the
point of the error.
% Invalid input detected at
‘^’marker.
Configuration Logging
You can log and view changes to the switch configuration. You can use the Configuration Change Logging
and Notification feature to track changes on a per-session and per-user basis. The logger tracks each
configuration command that is applied, the user who entered the command, the time that the command was
entered, and the parser return code for the command. This feature includes a mechanism for asynchronous
notification to registered applications whenever the configuration changes. You can choose to have the
notifications sent to the syslog.
Only CLI or HTTP changes are logged.Note
How to Use the CLI to Configure Features
Configuring the Command History
The software provides a history or record of commands that you have entered. The command history feature
is particularly useful for recalling long or complex commands or entries, including access lists. You can
customize this feature to suit your needs.
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 9
Using the Command-Line Interface
Configuration Logging

Changing the Command History Buffer Size
By default, the switch records ten command lines in its history buffer. You can alter this number for a current
terminal session or for all sessions on a particular line. This procedure is optional.
SUMMARY STEPS
1. terminal history [size number-of-lines]
DETAILED STEPS
PurposeCommand or Action
Changes the number of command lines that the switch records during
the current terminal session in the privileged EXEC mode. You can
configure the size from 0 through 256.
terminal history [size number-of-lines]
Example:
Switch# terminal history size 200
Step 1
Recalling Commands
To recall commands from the history buffer, perform one of the actions listed in this table. These actions are
optional.
The arrow keys function only on ANSI-compatible terminals such as VT100s.Note
SUMMARY STEPS
1. Ctrl-P or use the up arrow key
2. Ctrl-N or use the down arrow key
3. show history
DETAILED STEPS
PurposeCommand or Action
Recalls commands in the history buffer, beginning with the most recent command.
Repeat the key sequence to recall successively older commands.
Ctrl-P or use the up arrow key
Step 1
Returns to more recent commands in the history buffer after recalling commands
with Ctrl-P or the up arrow key. Repeat the key sequence to recall successively
more recent commands.
Ctrl-N or use the down arrow key
Step 2
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
10 OL-29043 -01
Using the Command-Line Interface
Configuring the Command History

PurposeCommand or Action
Lists the last several commands that you just entered in privileged EXEC mode.
The number of commands that appear is controlled by the setting of the terminal
show history
Example:
Switch# show history
Step 3
history global configuration command and the history line configuration
command.
Disabling the Command History Feature
The command history feature is automatically enabled. You can disable it for the current terminal session or
for the command line. This procedure is optional.
SUMMARY STEPS
1. terminal no history
DETAILED STEPS
PurposeCommand or Action
Disables the feature during the current terminal session in the
privileged EXEC mode.
terminal no history
Example:
Switch# terminal no history
Step 1
Enabling and Disabling Editing Features
Although enhanced editing mode is automatically enabled, you can disable it, and reenable it.
SUMMARY STEPS
1. terminal editing
2. terminal no editing
DETAILED STEPS
PurposeCommand or Action
Reenables the enhanced editing mode for the current terminal
session in the privileged EXEC mode.
terminal editing
Example:
Switch# terminal editing
Step 1
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 11
Using the Command-Line Interface
Enabling and Disabling Editing Features

PurposeCommand or Action
Disables the enhanced editing mode for the current terminal session
in the privileged EXEC mode.
terminal no editing
Example:
Switch# terminal no editing
Step 2
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
12 OL-29043 -01
Using the Command-Line Interface
Enabling and Disabling Editing Features

Editing Commands through Keystrokes
The keystrokes help you to edit the command lines. These keystrokes are optional.
The arrow keys function only on ANSI-compatible terminals such as VT100s.Note
Table 3: Editing Commands
DescriptionEditing Commands
Moves the cursor back one character.Ctrl-B or use the left arrow key
Moves the cursor forward one character.Ctrl-F or use the right arrow key
Moves the cursor to the beginning of the command
line.
Ctrl-A
Moves the cursor to the end of the command line.Ctrl-E
Moves the cursor back one word.Esc B
Moves the cursor forward one word.Esc F
Transposes the character to the left of the cursor with
the character located at the cursor.
Ctrl-T
Erases the character to the left of the cursor.Delete or Backspace key
Deletes the character at the cursor.Ctrl-D
Deletes all characters from the cursor to the end of
the command line.
Ctrl-K
Deletes all characters from the cursor to the beginning
of the command line.
Ctrl-U or Ctrl-X
Deletes the word to the left of the cursor.Ctrl-W
Deletes from the cursor to the end of the word.Esc D
Capitalizes at the cursor.Esc C
Changes the word at the cursor to lowercase.Esc L
Capitalizes letters from the cursor to the end of the
word.
Esc U
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 13
Using the Command-Line Interface
Enabling and Disabling Editing Features

Designates a particular keystroke as an executable
command, perhaps as a shortcut.
Ctrl-V or Esc Q
Scrolls down a line or screen on displays that are
longer than the terminal screen can display.
The More prompt is used for any output that
has more lines than can be displayed on the
terminal screen, including show command
output. You can use the Return and Space
bar keystrokes whenever you see the More
prompt.
Note
Return key
Scrolls down one screen.Space bar
Redisplays the current command line if the switch
suddenly sends a message to your screen.
Ctrl-L or Ctrl-R
Editing Command Lines That Wrap
You can use a wraparound feature for commands that extend beyond a single line on the screen. When the
cursor reaches the right margin, the command line shifts ten spaces to the left. You cannot see the first ten
characters of the line, but you can scroll back and check the syntax at the beginning of the command. The
keystroke actions are optional.
To scroll back to the beginning of the command entry, press Ctrl-B or the left arrow key repeatedly. You can
also press Ctrl-A to immediately move to the beginning of the line.
The arrow keys function only on ANSI-compatible terminals such as VT100s.Note
The following example shows how to wrap a command line that extend beyond a single line on the screen.
SUMMARY STEPS
1. access-list
2. Ctrl-A
3. Return key
DETAILED STEPS
PurposeCommand or Action
Displays the global configuration command entry that extends beyond
one line.
access-list
Example:
Switch(config)# access-list 101 permit tcp
Step 1
When the cursor first reaches the end of the line, the line is shifted ten
spaces to the left and redisplayed. The dollar sign ($) shows that the
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
14 OL-29043 -01
Using the Command-Line Interface
Enabling and Disabling Editing Features