Once you have successfully accessed the device, the CLI prompt displays in the terminal window of your console port or remote workstation as shown in the following example:
User Access Verification
login: admin
Password:<password>
Cisco Nexus Operating System (NX-OS) Software
TAC support: http://www.cisco.com/tac
Copyright (c) 2002-2009, Cisco Systems, Inc. All rights reserved.
The copyrights to certain works contained in this software are
owned by other third parties and used and distributed under
license. Certain components of this software are licensed under
the GNU General Public License (GPL) version 2.0 or the GNU
Lesser General Public License (LGPL) Version 2.1. A copy of each
such license is available at
http://www.opensource.org/licenses/gpl-2.0.php and
http://www.opensource.org/licenses/lgpl-2.1.php
switch#
You can change the default device hostname.
From the CLI prompt, you can do the following:
Use CLI commands for configuring features
Access the command history
Use command parsing functions
Note
In normal operation, usernames are case sensitive. However, when you are connected to the device through its console port, you can enter a login username in all uppercase letters regardless of how the username was defined. As long as you provide the correct password, the device logs you in.
Command Modes
This section describes command modes in the Cisco NX-OS CLI.
When you first log in, the Cisco NX-OS software places you in EXEC mode. The commands available in EXEC mode include the show commands that display the device status and configuration information, the clear commands, and other commands that perform actions that you do not save in the device configuration.
Global Configuration Command Mode
Global configuration mode provides access to the broadest range of commands. The term indicates characteristics or features that affect the device as a whole. You can enter commands in global configuration mode to configure your device globally, or to enter more specific configuration modes to configure specific elements such as interfaces or protocols.
SUMMARY STEPS
1.configure terminal
DETAILED STEPS
Command or Action
Purpose
Step 1
configure terminal
Example:
switch# configure terminal
switch(config)#
Enters global configuration mode.
Note
The CLI prompt changes to indicate that you are in global configuration mode.
Interface Configuration Command Mode
One example of a specific configuration mode that you enter from
global configuration mode is interface configuration mode. To configure
interfaces on your device, you must specify the interface and enter interface
configuration mode.
You must enable many features on a per-interface basis. Interface
configuration commands modify the operation of the interfaces on the device,
such as Ethernet interfaces or management interfaces (mgmt 0).
For more information about configuring interfaces, see the
Cisco Nexus Interfaces guide for your device.
Specifies the interface that you want to configure.
The CLI places you into interface configuration mode for the
specified interface.
Note
The CLI prompt changes to indicate that you are in interface
configuration mode.
Subinterface Configuration Command Mode
From global configuration mode, you can access a configuration submode
for configuring VLAN interfaces called subinterfaces. In subinterface
configuration mode, you can configure multiple virtual interfaces on a single
physical interface. Subinterfaces appear to a protocol as distinct physical
interfaces.
Subinterfaces also allow multiple encapsulations for a protocol on a
single interface. For example, you can configure IEEE 802.1Q encapsulation to
associate a subinterface with a VLAN.
For more information about configuring subinterfaces, see the Cisco Nexus Interfaces guide for your device.. For details about the subinterface commands, see the command reference guide for your device.
The CLI places you into a subinterface configuration mode for the
specified VLAN interface.
Note
The CLI prompt changes to indicate that you are in global
configuration mode.
Saving and Restoring a Command Mode
The Cisco NX-OS software allows you to save current command mode,
configure a feature, and then restore the previous command mode. The
push command saves the command mode and the
pop command restores the command mode.
The following example shows how to save and restore a command mode:
To exit from any configuration command mode, perform one of the
following tasks:
SUMMARY STEPS
1.exit
2.end
3.
(Optional) Ctrl-Z
DETAILED STEPS
Command or Action
Purpose
Step 1
exit
Example:
switch(config-if)# exit
switch(config)#
Exits from the current configuration command mode and
returns to the previous configuration command mode.
Step 2
end
Example:
switch(config-if)# end
switch#
Exits from the current configuration command mode and
returns to EXEC mode.
Step 3
Ctrl-Z
Example:
switch(config-if)# ^Z
switch#
(Optional)
Exits the current configuration command mode and returns to
EXEC mode.
Caution
If you use
Ctrl-Z at the end of a command line
in which a valid command has been typed, the CLI adds the command to the
running configuration file. In most cases, you should exit a configuration mode
using the
exit or
end command.
Command Mode Summary
This table summarizes information about the main command modes.
Table 1 Command Mode Summary
Mode
Access Method
Prompt
Exit Method
EXEC
From the login prompt, enter your username and password.
switch#
To exit to the login prompt, use the
exit command.
Global configuration
From EXEC mode, use the
configure terminal command.
switch(config)#
To exit to EXEC mode, use the
end or
exit command or press
Ctrl-Z.
Interface configuration
From global configuration mode, use an interface command and
specify an interface with an
interface command.
switch(config-if)#
To exit to global configuration mode, use the
exit command.
To exit to EXEC mode, use the
exit command or press
Ctrl-Z.
Subinterface configuration
From global configuration mode, specify a subinterface with an
interface command.
switch(config-subif)#
To exit to global configuration mode, use the
exit command.
To exit to EXEC mode, use the
end command or press
Ctrl-Z.
Special Characters
This table lists the characters that have special meaning in
Cisco NX-OS text strings and should be used only in regular expressions or other special contexts.
Table 2
Special Characters
Character
Description
%
Percent
#
Pound, hash, or number
...
Ellipsis
|
Vertical bar
< >
Less than or greater than
[ ]
Brackets
{ }
Braces
Keystroke Shortcuts
This table lists command key combinations that can be used in both EXEC and configuration modes.
Table 3
Keystroke Shortcuts
Keystokes
Description
Ctrl-A
Moves the cursor to the beginning of the line.
Ctrl-B
Moves the cursor one character to the left. When you enter a command that extends beyond a single line, you can press the Left Arrow or Ctrl-B keys repeatedly to scroll back toward the system prompt and verify the beginning of the command entry, or you can press the Ctrl-A key combination.
Ctrl-C
Cancels the command and returns to the command prompt.
Ctrl-D
Deletes the character at the cursor.
Ctrl-E
Moves the cursor to the end of the line.
Ctrl-F
Moves the cursor one character to the right.
Ctrl-G
Exits to the previous command mode without removing the command string.
Ctrl-K
Deletes all characters from the cursor to the end of the command line.
Ctrl-L
Redisplays the current command line.
Ctrl-N
Displays the next command in the command history.
Ctrl-O
Clears the terminal screen.
Ctrl-P
Displays the previous command in the command history.
Ctrl-R
Redisplays the current command line.
Ctrl-T
Transposes the character under the cursor with the character located to the right of the cursor. The cursor is then moved right one character.
Ctrl-U
Deletes all characters from the cursor to the beginning of the command line.
Ctrl-V
Removes any special meaning for the following keystroke. For example, press Ctrl-V before entering a question mark (?) in a regular expression.
Ctrl-W
Deletes the word to the left of the cursor.
Ctrl-X, H
Lists the history of commands you have entered.
When using this key combination, press and release the Ctrl and X keys together before pressing H.
Ctrl-Y
Recalls the most recent entry in the buffer (press keys simultaneously).
Ctrl-Z
Ends a configuration session, and returns you to EXEC mode.
When used at the end of a command line in which a valid command has been typed, the resulting configuration is first added to the running configuration file.
Up arrow key
Displays the previous command in the command history.
Down arrow key
Displays the next command in the command history.
Right arrow key
Left arrow key
Moves your cursor through the command string, either forward or backward, allowing you to edit the current command.
?
Displays a list of available commands.
Tab
Completes the word for you after entering the first characters of the word, and then pressing the Tab key. All options that match are presented.
Use tabs to complete the following items:
Command names
Scheme names in the file system
Server names in the file system
Filenames in the file system
Example:
switch(config)# xm<Tab>
switch(config)# xml<Tab>
switch(config)# xml server
switch# cd bootflash://mo<Tab>
bootflash://module-5/ bootflash://module-6/cv
switch# cd bootflash://module-
Abbreviating Commands
You can abbreviate commands and keywords by entering the first few characters of a command. The abbreviation must include sufficient characters to make it unique from other commands or keywords. If you are having trouble entering a command, check the system prompt and enter the question mark (?) for a list of available commands. You might be in the wrong command mode or using incorrect syntax.
This table lists examples of command abbreviations.
Table 4 Examples of Command Abbreviations
Command
Abbreviation
configure terminal
conf t
copy running-config startup-config
copy run start
interface ethernet 1/2
int e 1/2
show running-config
sh run
Completing a Partial Command Name
If you cannot remember a complete command name, or if you want to reduce the amount of typing you have to perform, enter the first few letters of the command, then press the Tab key. The command line parser will complete the command if the string entered is unique to the command mode. If your keyboard does not have a Tab key, press Ctrl-I instead.
The CLI recognizes a command once you have entered enough characters to make the command unique. For example, if you enter "conf" in EXEC mode, the CLI will be able to associate your entry with the configure command, because only the configure command begins with "conf".
In the following example the CLI recognizes the unique string for conf in EXEC mode when you press the Tab key:
switch# conf<Tab>
switch# configure
When you use the command completion feature the CLI displays the full command name. The CLI does not execute the command until you press the Return or Enter key. This allows you to modify the command if the full command was not what you intended by the abbreviation. If you enter a set of characters that could indicate more than one command, a list of matching commands displays.
For example, entering co<Tab> lists all commands available in EXEC mode beginning with "co":
switch# co<Tab>
configure copy
switch# co
Note that the characters you entered appear at the prompt again to allow you to complete the command entry.
Identifying Your Location in the Command Hierarchy
Some features have a configuration submode hierarchy nested more than
one level. In these cases, you can display information about your present
working context (PWC).
Almost every configuration command has a no form that can be used to disable a feature, revert to a default value, or remove a configuration. The Cisco NX-OS command reference publications describe the function of the no form of the command whenever a no form is available.
This example shows how to disable a feature:
switch# configure terminal
switch(config)# feature tacacs+
switch(config)# no feature tacacs+
This example shows how to revert to the default value for a feature:
switch# configure terminal
switch(config)# banner motd #Welcome to the switch#
switch(config)# show banner motd
Welcome to the switch
switch(config)# no banner motd
switch(config)# show banner motd
User Access Verification
This example shows how to remove the configuration for a feature:
switch# configure terminal
switch(config)# radius-server host 10.10.2.2
switch(config)# show radius-server
retransmission count:0
timeout value:1
deadtime value:1
total number of servers:1
following RADIUS servers are configured:
10.10.1.1:
available for authentication on port:1812
available for accounting on port:1813
10.10.2.2:
available for authentication on port:1812
available for accounting on port:1813
switch(config)# no radius-server host 10.10.2.2
switch(config)# show radius-server
retransmission count:0
timeout value:1
deadtime value:1
total number of servers:1
following RADIUS servers are configured:
10.10.1.1:
available for authentication on port:1812
available for accounting on port:1813
This example shows how to use the no form of a command in EXEC mode:
switch# cli var name testinterface ethernet1/2
switch# show cli variables
SWITCHNAME="switch"
TIMESTAMP="2009-05-12-13.43.13"
testinterface="ethernet1/2"
switch# cli no var name testinterface
switch# show cli variables
SWITCHNAME="switch"
TIMESTAMP="2009-05-12-13.43.13"
Configuring CLI Variables
This section describes CLI variables in the Cisco NX-OS CLI.
The Cisco NX-OS software supports the definition and use of variables in CLI commands.
You can refer to CLI variables in the following ways:
Entered directly on the command line.
Passed to a script initiated using the run-script command. The variables defined in the parent shell are available for use in the child run-script command process.
CLI variables have the following characteristics:
Cannot have nested references through another variable
Can persist across switch reloads or exist only for the current session
Cisco NX-OS supports one predefined variable: TIMESTAMP. This variable refers to the current time when the command executes in the format YYYY-MM-DD-HH.MM.SS.
Note
The TIMESTAMP variable name is case sensitive. All letters must be uppercase.
Configuring CLI Session-Only Variables
You can define CLI session variables to persist only for the duration of your CLI session. These variables are useful for scripts that you execute periodically. You can reference the variable by enclosing the name in parentheses and preceding it with a dollar sign ($), for example $(variable-name).
SUMMARY STEPS
1.cli var name variable-name variable-text
2.
(Optional) show cli variables
DETAILED STEPS
Command or Action
Purpose
Step 1
cli var name variable-name variable-text
Example:
switch# cli var name testinterface ethernet 2/1
Configures the CLI session variable. The variable-name argument is alphanumeric, case sensitive, and has a maximum length of 31 characters. The variable-text argument is alphanumeric, case sensitive, can contain spaces, and has a maximum length of 200 characters.
Step 2
show cli variables
Example:
switch# show cli variables
(Optional)
Displays the CLI variable configuration.
Configuring Persistent CLI Variables
You can configure CLI variables that persist across CLI sessions and device reloads.
SUMMARY STEPS
1.configure terminal
2.cli var namevariable-namevariable-text
3.exit
4.
(Optional) show cli variables
5.
(Optional) copy running-config startup-config
DETAILED STEPS
Command or Action
Purpose
Step 1
configure terminal
Example:
switch# configure terminal
switch(config)#
Enters global configuration mode.
Step 2
cli var namevariable-namevariable-text
Example:
switch(config)# cli var name testinterface ethernet 2/1
Configures the CLI persistent variable. The variable name is case-sensitive alphanumeric string and must begin with an alphabetic character. The maximum length is 31 characters.
You can define command aliases to replace frequently used commands. The command aliases can represent all or part of the command syntax.
Command alias support has the following characteristics:
Command aliases are global for all user sessions.
Command aliases persist across reboots if you save them to the startup configuration.
Command alias translation always takes precedence over any keyword in any configuration mode or submode.
Command alias configuration takes effect for other user sessions immediately.
The Cisco NX-OS software provides one default alias, alias, which is the equivalent to the show cli alias command that displays all user-defined aliases.
You cannot delete or change the default command alias alias.
You can nest aliases to a maximum depth of 1. One command alias can refer to another command alias that must refer to a valid command, not to another command alias.
A command alias always replaces the first command keyword on the command line.
You can define command aliases for commands in any command mode.
If you reference a CLI variable in a command alias, the current value of the variable appears in the alias, not the variable reference.
You can use command aliases for show command searching and filtering.
Defining Command Aliases
You can define command aliases for commonly used commands.
SUMMARY STEPS
1.configure terminal
2.cli alias namealias-name alias-text
3.exit
4.
(Optional) alias
5.
(Optional) copy running-config startup-config
DETAILED STEPS
Command or Action
Purpose
Step 1
configure terminal
Example:
switch# configure terminal
switch(config)#
Enters global configuration mode.
Step 2
cli alias namealias-name alias-text
Example:
switch(config)# cli alias name ethint interface ethernet
Configures the command alias. The alias name is an alphanumeric string that is not case sensitive and must begin with an alphabetic character. The maximum length is 30 characters.
Step 3
exit
Example:
switch(config)# exit
switch#
Exits global configuration mode.
Step 4
alias
Example:
switch# alias
(Optional)
Displays the command alias configuration.
Step 5
copy running-config startup-config
Example:
switch# copy running-config startup-config
(Optional)
Copies the running configuration to the startup configuration.
Configuring Command Aliases for a User Session
You can create a command alias for the current user session which is not available to any other user on the Cisco NX-OS device. You can also save the command alias for future use by the current user account.
SUMMARY STEPS
1.terminal alias [persist] alias-namecommand -string
DETAILED STEPS
Command or Action
Purpose
Step 1
terminal alias [persist] alias-namecommand -string
Example:
switch# terminal alias shintbr show interface brief
Configures a command alias for the current user session. Use the persist keyword to save the alias for future use by the user account.
Note
Do not abbreviate the persist keyword.
Command Scripts
This section describes how you can create scripts of commands to perform multiple tasks.
You can create a list of commands in a file and execute them from the CLI. You can use CLI variables in the command script.
Note
You cannot create the script files at the CLI prompt. You can create the script file on a remote device and copy it to the bootflash:, slot0:, or volatile: directory on the Cisco NX-OS device.
Executes the commands in the file on the default directory.
Echoing Information to the Terminal
You can echo information to the terminal, which is particularly useful from a command script. You can reference CLI variables and use formatting options in the echoed text.
This table lists the formatting options that you can insert in the text.
Table 5
Formatting Options for the echo Command
Formatting Option
Description
\b
Inserts back spaces.
\c
Removes the new line character at the end of the text string.
\f
Inserts a form feed character.
\n
Inserts a new line character.
\r
Returns to the beginning of the text line.
\t
Inserts a horizontal tab character.
\v
Inserts a vertical tab character.
\\
Displays a backslash character.
\nnn
Displays the corresponding ASCII octal character.
SUMMARY STEPS
1.echo [backslash-interpret] [text]
DETAILED STEPS
Command or Action
Purpose
Step 1
echo [backslash-interpret] [text]
Example:
switch# echo This is a test.
This is a test.
The backslash-interpret keyword indicates that the text string contains formatting options. The text argument is alphanumeric, case sensitive, and can contain blanks. The maximum length is 200 characters. The default is a blank line.
Delaying Command Action
You can delay a command action for a period of time, which is particularly useful within a command script.
SUMMARY STEPS
1.sleepseconds
DETAILED STEPS
Command or Action
Purpose
Step 1
sleepseconds
Example:
switch# sleep 30
Causes a delay for a number of seconds. The range is from 0 to 2147483647.
Context-Sensitive Help
The
Cisco NX-OS software provides context-sensitive help in the CLI. You can use a question mark (?) at any point in a command to list the valid input options.
CLI uses the caret (^) symbol to isolate input errors. The ^ symbol appears at the point in the command string where you have entered an incorrect command, keyword, or argument.
This table shows example outputs of context sensitive help.
Table 6
Context-Sensitive Help Example
Example Outputs
Description
switch# clock ?
set HH:MM:SS Current Time
switch# clock
Displays the command syntax for the clock command in EXEC mode.
The switch output shows that the set keyword is required for using the clock command.
switch# clock set ?
WORD HH:MM:SS Current Time
switch# clock set
Displays the command syntax for setting the time.
The help output shows that the current time is required for setting the clock and how to format the time.
switch# clock set 13:32:00<CR>
% Incomplete command
switch#
Adds the current time.
The CLI indicates the command is incomplete.
switch# <Ctrl-P>
switch# clock set 13:32:00
Displays the previous command that you entered.
switch# clock set 13:32:00 ?
<1-31> Day of the month
switch# clock set 13:32:00
Displays the additional arguments for the clock set command.
switch# clock set 13:32:00 18 ?
April Month of the year
August Month of the year
December Month of the year
February Month of the year
January Month of the year
July Month of the year
June Month of the year
March Month of the year
May Month of the year
November Month of the year
October Month of the year
September Month of the year
switch# clock set 13:32:00 18
Displays the additional arguments for the clock set command.
switch# clock set 13:32:00 18 April 08<CR>
% Invalid input detected at '^' marker.
Adds the date to the clock setting.
The CLI indicates an error with the caret symbol (^) at 08.
switch# clock set 13:32:00 18 April ?
<2000-2030> Enter the year (no abbreviation)
switch# clock set 13:32:00 18 April
Displays the correct arguments for the year.
switch# clock set 13:32:00 18 April 2008<CR>
switch#
Enters the correct syntax for the clock set command.
Understanding Regular Expressions
The Cisco NX-OS software supports regular expressions for searching and filtering in CLI output, such as the show commands. Regular expressions are case sensitive and allow for complex matching requirements.
You can also use other keyboard characters (such as ! or ~) as single-character patterns, but certain keyboard characters have special meanings when used in regular expressions.
This table lists the keyboard characters that have special meanings.
Table 7 Special Characters with Special Meaning
Character
Special Meaning
.
Matches any single character, including white space.
*
Matches 0 or more sequences of the pattern.
+
Matches 1 or more sequences of the pattern.
?
Matches 0 or 1 occurrences of the pattern.
^
Matches the beginning of the string.
$
Matches the end of the string.
_ (underscore)
Matches a comma (,), left brace ({), right brace (}), left parenthesis ( ( ), right parenthesis ( ) ), the beginning of the string, the end of the string, or a space.
Note
The underscore is only treated as a regular expression for BPG related commands
To use these special characters as single-character patterns, remove the special meaning by preceding each character with a backslash (\). This example contains single-character patterns that match a dollar sign ($), an underscore (_), and a plus sign (+), respectively:
\$ \_ \+
Multiple-Character Patterns
You can also specify a pattern that contains multiple characters by joining letters, digits, or keyboard characters that do not have special meanings. For example, a4% is a multiple-character regular expression.
With multiple-character patterns, the order is important. The regular expression a4% matches the character a followed by a 4 followed by a percent sign (%). If the string does not have a4%, in that order, pattern matching fails. The multiple-character regular expression a. (the character a followed by a period) uses the special meaning of the period character to match the letter a followed by any single character. With this example, the strings ab, a!, or a2 are all valid matches for the regular expression.
You can remove the special meaning of a special character by inserting a backslash before it. For example, when the expression a\. is used in the command syntax, only the string a. will be matched.
Anchoring
You can match a regular expression pattern against the beginning or the end of the string by anchoring these regular expressions to a portion of the string using the special characters.
This table lists the special characters that you can use for anchoring.
Table 8 Special Characters Used for Anchoring
Character
Description
^
Matches the beginning of the string.
$
Matches the end of the string.
For example, the regular expression ^con matches any string that starts with "con", and sole$ matches any string that ends with "sole".
Note
The ^ symbol can also be used to indicate the logical function "not" when used in a bracketed range. For example, the expression [^abcd] indicates a range that matches any single letter, as long as it is not a, b, c, or d.
Searching and Filtering show Command Output
Often, the output from
show commands can be lengthy and cumbersome. The
Cisco NX-OS software provides the means to search and filter the output so that
you can easily locate information. The searching and filtering options follow a
pipe character (|) at the end of the
show command. You can display the options using the
using the CLI context-sensitive help facility:
switch# show running-config | ?
cut Print selected parts of lines.
diff Show difference between current and previous invocation (creates temp files:
remove them with 'diff-clean' command and don't use it on commands with big
outputs, like 'show tech'!)
egrep Egrep - print lines matching a pattern
grep Grep - print lines matching a pattern
head Display first lines
human Output in human format
last Display last lines
less Filter for paging
no-more Turn-off pagination for command output
perl Use perl script to filter output
section Show lines that include the pattern as well as the subsequent lines that are
more indented than matching line
sed Stream Editor
sort Stream Sorter
sscp Stream SCP (secure copy)
tr Translate, squeeze, and/or delete characters
uniq Discard all but one of successive identical lines
vsh The shell that understands cli command
wc Count words, lines, characters
xml Output in xml format (according to .xsd definitions)
begin Begin with the line that matches
count Count number of lines
end End with the line that matches
exclude Exclude lines that match
include Include lines that match
The Cisco NX-OS CLI provides a set of keywords that you can use with
the
show commands to search and filter the command
output.
This table lists the keywords for filtering and searching the CLI
output.
Table 9 Filtering and Searching Keywords
Keyword Syntax
Description
beginstring
Example:
show version | begin Hardware
Starts displaying at the line that contains the text that
matches the search string. The search string is case sensitive.
count
Example:
show running-config | count
Displays the number of lines in the command output.
cut [-dcharacter] {-b |
-c |
-f |
-s}
Example:
show file testoutput | cut -b 1-10
Displays only the part of the output lines. You can display a
number of bytes (-b), characters
(-vcut [-dcharacter] {-b |
-c |
-f |
-s}), or fields
(-f). You can also use the
-d keyword to define a field
delimiter other than the tag character default. The
-s keyword suppress the display of
line not containing the delimiter.
endstring
Example:
show running-config | end interface
Displays all lines up to the last occurrence of the search
string.
excludestring
Example:
show interface brief | exclude down
Displays all lines that do not include the search string. The
search string is case sensitive.
head [lineslines]
Example:
show logging logfile | head lines 50
Displays the beginning of the output for the number of lines
specified. The default number of lines is 10.
human
Example:
show version | human
Displays the output in normal format if you have previously
set the output format to XML using the
terminal output xml command.
includestring
Example:
show interface brief | include up
Displays all lines that include the search string. The search
string is case sensitive.
last [lines]
Example:
show logging logfile | last 50
Displays the end of the output for the number of lines
specified. The default number of lines is 10.
no-more
Example:
show interface brief | no-more
Displays all the output without stopping at the end of the
screen with the ––More–– prompt.
sscpSSH-connection-namefilename
Example:
show version | sscp MyConnection
show_version_output
Redirects the output using streaming secure copy (sscp) to a
named SSH connection. You can create the SSH named connection using the
ssh name command.
wc [bytes |
lines |
words]
Example:
show file testoutput | wc bytes
Displays counts of characters, lines, or words. The default is
to display the number of lines, words, and characters.
xml
Example:
show version | xml
Displays the output in XML format.
diff Utility
You can compare the output from a
show command with the output from the previous
invocation of that command.
Caution
Do not use the diff utility for
show commands that have very long output, such as
the
show tech-support command.
This table describes the keywords for the diff utility.
Table 10 diff Utility Keywords
Keyword
Description
--left-column
Prints only the left column of the two common
lines in side-by-side format.
-B
Ignores the changes that only insert or delete
blank lines.
-I
Ignores the changes that only insert or delete
lines that match the regular expression.
-Wcolumns
Specifies the output column width for the
side-by-side format. The range is from 0 to 4294967295.
-b
Ignores the changes in the amount of white
space. The default is to display the white space differences.
-clines
Sets the number of lines of context displayed.
The default number of lines is 3. The range is from 0 to 4294967295.
-I
Ignores uppercase and lowercase differences.
The default is to report the uppercase and lowercase differences.
-q
Indicates whether the files differ but does not
display the details of the differences. The default is to display the
differences.
-s
Indicates whether the two outputs are the same.
The default is no indication when the outputs are the same.
-y
Uses the side-by-side format for the output
differences. The default is to display the old output lines first, followed by
the current output lines.
again
Does not create new output file: use old ones,
just change display options or add more filters.
echo
Echoes the current command output. This keyword
is only effective when there is no previous command output.
The Cisco NX-OS software creates temporary files for the most current
output for a
show command for all current and previous users
sessions. You can remove these temporary files using the
diff-clean command.
diff-clean [all-sessions |
all-users]
By default, the
diff-clean command removes the temporary files for the
current user's active session. The
all-sessions keyword removes temporary files
for all past and present sessions for the current user. The
all-users keyword removes temporary files for
all past and present sessions for the all users.
grep and egrep Utilities
You can use the Global Regular Expression Print (grep) and Extended grep (egrep) command-line utilities to filter the show command output.
Specifies to ignore the case difference in matched lines.
invert-match
Displays lines that do not match the expression.
line-exp
Displays only lines that match a complete line.
line-number
Specifies to display the line number before each matched line.
nextlines
Specifies the number of lines to display after a matched line. The default is 0. The range is from 1 to 999.
prevlines
Specifies the number of lines to display before a matched line. The default is 0. The range is from 1 to 999.
word-exp
Displays only lines that match a complete word.
expression
Specifies a regular expression for searching the output.
less Utility
You can use the less utility to display the contents of the show command output one screen at a time. You can enter less commands at the : prompt. To display all less commands you can use, enter h at the : prompt.
sed Utility
You can use the Stream Editor (sed) utility to filter and manipulate the show command output as follows:
sedcommand
The command argument contains sed utility commands.
sort Utility
You can use the sort utility to filter
show command output.
This table describes the sort utiliity parameters.
Table 12 sort Utility Parameters
Parameter
Description
-M
Sorts by month.
-b
Ignores leading blanks (space characters). The default sort
includes the leading blanks.
-d
Sorts by comparing only blanks and alphanumeric characters. The
default sort includes all characters.
-f
Folds lowercase characters into uppercase characters.
-g
Sorts by comparing a general numeric value.
-i
Sorts only using printable characters. The default sort includes
nonprintable characters.
-kfield-number[.char-position][ordering]
Sorts according to a key value. There is no default key value.
-n
Sorts according to a numeric string value.
-r
Reverses order of the sort results. The default sort output is
in ascending order.
-tdelimiter
Sorts using a specified delimiter. The default delimiter is the
space character.
-u
Removes duplicate lines from the sort results. The sort output
displays the duplicate lines.
Searching and Filtering from the --More-- Prompt
You can search and filter output from --More– prompts in the show command output.
This table describes the --More– prompt commands.
Table 13
--More-- Prompt Commands
Commands
Description
[lines]<space>
Displays output lines for either the specified number of lines or the current screen size.
[lines]z
Displays output lines for either the specified number of lines or the current screen size. If you use the lines argument, that value becomes the new default screen size.
[lines]<return>
Displays output lines for either the specified number of lines or the current default number of lines. The initial default is 1 line. If you use the optional lines argument, that value becomes the new default number of lines to display for this command.
[lines]d or [lines]Ctrl+shift+D
Scrolls through output lines for either the specified number of lines or the current default number of lines. The initial default is 11 lines. If you use the optional lines argument, that value becomes the new default number of lines to display for this command.
q or Q or Ctrl-C
Exits the --More– prompt.
[lines]s
Skips forward in the output for either the specified number of lines or the current default number of lines and displays a screen of lines. The default is 1 line.
[lines]f
Skips forward in the output for either the specified number of screens or the current default number of screens and displays a screen of lines. The default is 1 screen.
=
Displays the current line number.
[count]/expression
Skips to the line that matches the regular expression and displays a screen of output lines. Use the optional count argument to search for lines with multiple occurrences of the expression. This command sets the current regular expression that you can use in other commands.
[count]n
Skips to the next line that matches the current regular expression and displays a screen of output lines. Use the optional count argument to skip past matches.
{! | :![shell-cmd]}
Executes the command specified in the shell-cmd argument in a subshell.
.
Repeats the previous command.
Using the Command History
The Cisco NX-OS software CLI allows you to access the command history
for the current user session. You can recall and reissue commands, with or
without modification. You can also clear the command history.
You can recall a command in the command history to optionally modify and
enter again.
This example shows how to recall a command and reenter it:
switch(config)# show cli history
0 11:04:07 configure terminal
1 11:04:28 show interface ethernet 2/24
2 11:04:39 interface ethernet 2/24
3 11:05:13 no shutdown
4 11:05:19 exit
5 11:05:25 show cli history
switch(config)# !1
switch(config)# show interface ethernet 2/24
You can also use the
Ctrl-P and
Ctrl-N keystroke shortcuts to recall commands.
Controlling CLI History Recall
You can control the commands that you recall from the CLI history
using the
Ctrl-P and
Ctrl-N keystroke shortcuts. TheBy default, the Cisco
NX-OS software recalls all commands from the current command mode and higher
command modes. For example, if you are working in global configuration mode,
the command recall keystroke shortcuts recall both EXEC mode and global
configuration mode commands. Using the
terminal history no-exec-in-config command, you can
avoid recalling EXEC mode commands when you are in a configuration mode.
SUMMARY STEPS
1.[no]
terminal history no-exec-in-config
DETAILED STEPS
Command or Action
Purpose
Step 1
[no]
terminal history no-exec-in-config
Example:
switch# terminal history no-exec-in-config
Configures the CLI history to remove the EXEC commands when you
use the recall keystroke shortcuts in a configuration mode. The default recalls
EXEC commands. You can revert to the default using the
no form of the command.
Configuring the CLI Edit Mode
You can recall commands from the CLI history using the
Ctrl-P and
Ctrl-N keystroke shortcuts and edit them before
reissuing them. The default edit mode is emacs. You can change the edit mode to
vi.
SUMMARY STEPS
1.[no]
terminal edit-mode vi [persist]
DETAILED STEPS
Command or Action
Purpose
Step 1
[no]
terminal edit-mode vi [persist]
Example:
switch# terminal edit-mode vi
Changes the CLI edit mode to vi for the user session. The
persist keyword makes the setting
persistent across sessions for the current username.
Use the
no to revert to using emacs.
Displaying the Command History
You can display the command history using the
show cli history command.
The
show cli history command has the following syntax:
show cli history [lines] [unformatted]
show cli history [lines]
[config-only |
exec-only |
this-mode-only] [unformatted]
By default, the number of lines displayed is 12 and the output includes
the command number and timestamp.
The example shows how to display default number of lines of the command
history:
switch# show cli history
The example shows how to display 20 lines of the command history:
switch# show cli history 20
The example shows how to display only the configuration commands in the
command history:
switch(config)# show cli history config-only
The example shows how to display only the EXEC commands in the command
history:
switch(config)# show cli history exec-only
The example shows how to display only the commands in the command
history for the current command mode:
switch(config-if)# show cli history this-mode-only
The example shows how to display only the commands in the command
history without the command number and timestamp:
switch(config)# show cli history unformatted
Enabling or Disabling the CLI Confirmation Prompts
For many features, the Cisco NX-OS software displays prompts on the
CLI that ask for confirmation before continuing. You can enable or disable
these prompts. The default is enabled.
SUMMARY STEPS
1.[no]
terminal dont-ask [persist]
DETAILED STEPS
Command or Action
Purpose
Step 1
[no]
terminal dont-ask [persist]
Example:
switch# terminal dont-ask
Disables the CLI confirmation prompt. The
persist keyword makes the setting
persistent across sessions for the current username. The default is enabled.
Use the
no form of the command to enable the CLI
confirmation prompts.
Setting CLI Display Colors
You can change the CLI colors to display as follows:
The prompt displays in green if the previous command succeeded.
The prompt displays in red of the previous command failed.
The user input displays in blue.
The command output displays in the default color.
The default colors are those sent by the terminal emulator software.
SUMMARY STEPS
1.terminal color [evening]
[persist]
DETAILED STEPS
Command or Action
Purpose
Step 1
terminal color [evening]
[persist]
Example:
switch# terminal color
Sets the CLI display colors for the terminal session. The
evening keyword is not supported. The
persist keyword makes the setting
persistent across sessions for the current username. The default setting is not
persistent.
Sending Commands to Modules
You can send commands directly to modules from the supervisor module
session using the
slot command.
The
slot has the following syntax:
slotslot-number [quoted]
command-string
By default, the keyword and arguments in the
command-string argument are space-separated. To send
more than one command to a module, separate the commands with a space
character, a semicolon character (;), and a space character.
The
quoted keyword indicates that the command string begins
and ends with double quotation marks ("). Use this keyword when you want to
redirect the module command output to a filtering utility, such as diff, that
is only supported on the supervisor module session.
The following example shows how to display and filter module
information:
switch# slot 2 show version | grep lc
The following example shows how to filter module information on the
supervisor module session:
When the supervisor modules power up, a specialized BIOS image
automatically loads and tries to locate a valid kickstart image for booting the
system. If a valid kickstart image is not found, the following BIOS loader
prompt displays:
loader>
For information on how to load the Cisco NX-OS software from th loader> prompt, see the Cisco Nexus Troubleshooting guide for your device.
You can reference a variable using the syntax $(variable-name).
This example shows how to reference a user-defined CLI session variable:
switch# show interface $(testinterface)
Ethernet2/1 is down (Administratively down)
Hardware is 10/100/1000 Ethernet, address is 0000.0000.0000 (bia 0019.076c.4dac)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA
auto-duplex, auto-speed
Beacon is turned off
Auto-Negotiation is turned on
Input flow-control is off, output flow-control is off
Auto-mdix is turned on
Switchport monitor is off
Last clearing of "show interface" counters never
5 minute input rate 0 bytes/sec, 0 packets/sec
5 minute output rate 0 bytes/sec, 0 packets/sec
L3 in Switched:
ucast: 0 pkts, 0 bytes - mcast: 0 pkts, 0 bytes
L3 out Switched:
ucast: 0 pkts, 0 bytes - mcast: 0 pkts, 0 bytes
Rx
0 input packets 0 unicast packets 0 multicast packets
0 broadcast packets 0 jumbo packets 0 storm suppression packets
0 bytes
Tx
0 output packets 0 multicast packets
0 broadcast packets 0 jumbo packets
0 bytes
0 input error 0 short frame 0 watchdog
0 no buffer 0 runt 0 CRC 0 ecc
0 overrun 0 underrun 0 ignored 0 bad etype drop
0 bad proto drop 0 if down drop 0 input with dribble
0 input discard
0 output error 0 collision 0 deferred
0 late collision 0 lost carrier 0 no carrier
0 babble
0 Rx pause 0 Tx pause 0 reset
Using the System-Defined Timestamp Variable
This example uses $(TIMESTAMP) when redirecting show command output to a file:
switch# show running-config > rcfg.$(TIMESTAMP)
Preparing to copy....done
switch# dir
12667 May 01 12:27:59 2008 rcfg.2008-05-01-12.27.59
Usage for bootflash://sup-local
8192 bytes used
20963328 bytes free
20971520 bytes total
Running a Command Script
This example displays the CLI commands specified in the script file:
switch# show file testfile
configure terminal
interface ethernet 2/1
no shutdown
end
show interface ethernet 2/1
This example displays the run-script command execution output:
switch# run-script testfile
`configure terminal`
`interface ethernet 2/1`
`no shutdown`
`end`
`show interface ethernet 2/1 `
Ethernet2/1 is down (Link not connected)
Hardware is 10/100/1000 Ethernet, address is 0019.076c.4dac (bia 0019.076c.4dac)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA
Port mode is trunk
auto-duplex, auto-speed
Beacon is turned off
Auto-Negotiation is turned on
Input flow-control is off, output flow-control is off
Auto-mdix is turned on
Switchport monitor is off
Last clearing of "show interface" counters 1d26.2uh
5 minute input rate 0 bytes/sec, 0 packets/sec
5 minute output rate 0 bytes/sec, 0 packets/sec
Rx
0 input packets 0 unicast packets 0 multicast packets
0 broadcast packets 0 jumbo packets 0 storm suppression packets
0 bytes
Tx
0 output packets 0 multicast packets
0 broadcast packets 0 jumbo packets
0 bytes
0 input error 0 short frame 0 watchdog
0 no buffer 0 runt 0 CRC 0 ecc
0 overrun 0 underrun 0 ignored 0 bad etype drop
0 bad proto drop 0 if down drop 0 input with dribble
0 input discard
0 output error 0 collision 0 deferred
0 late collision 0 lost carrier 0 no carrier
0 babble
0 Rx pause 0 Tx pause 0 reset
Additional References for the CLI
This section includes additional information related to the CLI.