Command Line Interface
You can configure the Cisco Nexus 3550-T Programmable Switch Platform via the CLI. You can access this interface via SSH, telnet, or an industry standard serial interface.
Configuration Mode
By using the CLI, you can inspect the current configurations of the Nexus 3550-T and also modify the configuration.
You can use the CLI in either a modal or non-modal way. For example, commands that
change the current configuration are prefixed with config
. When executing
multiple configuration commands, it is convenient to enter config mode. For example, to disable an interface, enter the following command:
admin@NX-3550-T# configure interface ethernet1 shutdown
Interface "ethernet1" disabled
Alternatively, enter the config mode and then disable the interface:
admin@NX-3550-T# config
admin@NX-3550-T(config)# interface ethernet1 shutdown
Interface "ethernet1" disabled
Note
In the above example the CLI prompt indicates that config mode is in use.
To exit the mode, simply type exit
.
admin@NX-3550-T(config)# exit
admin@NX-3550-T#
Additionally, a shortcut is available to exit any mode, which is by pressing Control+d
.
Note
When you exit the config mode, the interface drops back to the default mode. Importantly, if you type exit
within the default mode, you will log you out of the device.
You can nest modal states. When you use the exit
command, you drop out of that level and go up to the previous level. To drop out of all levels and return to the top modal level, use the end
command.
admin@NX-3550-T# config
admin@NX-3550-T(config)# interface ethernet1
admin@NX-3550-T(config-if-et1)# end
admin@NX-3550-T#
Help and Autocompletion
The CLI includes help and tab autocompletion.
Help
While using the Nexus 3550-T, access the help by entering the ?
command. If multiple parameter options that are valid from that point on are available, entering ?
will list
those options.
admin@NX-3550-T# configure interface management1 ?
interface Configure interfaces
exit Exit management network configuration mode
end Exit configuration mode
no Negate a command or set to defaults
ip Configure IPv4 settings
ipv6 Configure IPv6 settings
If no further valid parameter options are available when you enter ?
, the detailed usage information is displayed:
admin@NX-3550-T# configure interface management1 ip address ?
<a.b.c.d/n> IPv4 address and prefix length
Autocompletion
For autocompletion and to get suggestions for any command, press tab after entering any partial command. In this example, the interface shows a list of available ports after you press tab:
admin@NX-3550-T# config interface
ethernet1 ethernet2 ethernet3 ethernet4 ethernet5 ethernet6
ethernet7 ethernet8 ethernet9 ethernet10 ethernet11 ethernet12
ethernet13 ethernet14 ethernet15 ethernet16 ethernet17 ethernet18
ethernet19 ethernet20 ethernet21 ethernet22 ethernet23 ethernet24
ethernet25 ethernet26 ethernet27 ethernet28 ethernet29 ethernet30
ethernet31 ethernet32 ethernet33 ethernet34 ethernet35 ethernet36
ethernet37 ethernet38 ethernet39 ethernet40 ethernet41 ethernet42
ethernet43 ethernet44 ethernet45 ethernet46 ethernet47 ethernet48
vlan1 vlan10 vlan100 breakout management1 management2
Command Pipelines
The CLI supports redirecting command output to standard
UNIX utilities, such as grep
and less
.
admin@NX-3550-T# show interface ethernet1 | grep Speed
Speed is 10000 Mbps
Because this feature allows you to run arbitrary shell commands, it is available only to users who have admin
privileges.
SSH Keys
To authenticate your login into the Nexus 3550-T, you can use SSH keys, rather than entering a password. To authenticate with SSH keys, add your public key into the Nexus 3550-T, for example:
admin@NX-3550-T# config user admin sshkey "ssh-rsa AAAAB3NzaC1yc2EAAAA
DAQABAAABAQC15sjG4cYSAbYU0VIwPkdQkIKb0A2xxhPCjOAnzt91CrRQZibirZNqqW71TX3QVt
Ruqp2ZQjo19Nd9bk2iwa3qDITQIOlRdSJgwEBdklfgjkrjkd8KLSDfklwjkrjksjkXyztI3sKRM
mcYOEFjt9Bv+5JPw3o3Pja5GQOO5VEjM//QhsbMZ+G/4Sfx5GiLTaktenqNWflPaMcDWqq1wuuf
6mG7lEM55UDp5xWRrh5vIfyOh9Llosdfsasjkejk89sv9+cjkfhjksjhcjkhskhkljashdfiuhs
dfv98734kjFDjhjhdjhbfjh489jkJKZDJKHFVjkhi6SBbTu5v9 bob@myserver.com"
Added ssh key for user "admin"
After configuring the SSH keys, you can login without being prompted for a password.
$ ssh admin@NX-3550-T
admin@NX-3550-T>
To remove an SSH key for a user, use the 'no-' form of the sshkey
command, and pass the public key that you need to remove.
admin@NX-3550-T> config user admin no sshkey "ssh-rsa AAAAB3NzaC1yc2EA
AAADAQABAAABAQC15sjG4cYSAbYU0VIwPkdQkIKb0A2xxhPCjOAnzt91CrRQZibirZNqqW71TX3
QVtRuqp2ZQjo19Nd9bk2iwa3qDITQIOlRdSJgwEBdklfgjkrjkd8KLSDfklwjkrjksjkXyztI3s
KRMmcYOEFjt9Bv+5JPw3o3Pja5GQOO5VEjM//QhsbMZ+G/4Sfx5GiLTaktenqNWflPaMcDWqq1w
uuf6mG7lEM55UDp5xWRrh5vIfyOh9Llosdfsasjkejk89sv9+cjkfhjksjhcjkhskhkljashdfi
uhsdfv98734kjFDjhjhdjhbfjh489jkJKZDJKHFVjkhi6SBbTu5v9 bob@myserver.com"
Removed ssh key for user "admin"
This page was last updated on Mar-23-2021.