Filter
Top Products
50 Using the Command Line Interface
TACACS Config Mode. Use this mode to configure the connection parameters to a
TACACS+ user authentication server.
VLAN Mode. (formally called the Interface Vlan Config mode, or more simply, the
Interface Vlan mode) This mode groups all the commands pertaining to VLANs.
Command Prompt: hostname (conf-if-vl-vlan-id)#
Flow of CLI Operation
1. You log into the CLI session and enter the User Exec mode. In the User Exec
mode, the “hostname >” prompt is displayed on the screen.
The parsing process is initiated whenever you type a command and press
ENTER. The command tree is searched for the command of interest. If the com-
mand is not found, the output message indicates where the offending entry begins.
For instance, the Privileged Exec mode has the command show arp brief. If you
attempt to execute the command, but you enter an extra “p” in “arpp”, then the
output message displays the ^ marker under the extra “p”, followed by
“$%Invalid input detected at '^' marker.”
Another typical case when an error message appears is when you have entered an
invalid input parameter in the command. The ^ marker shows where in the com-
mand the first character of invalid input was detected.
After all the mandatory parameters are entered, any additional parameters entered
are treated as optional parameters. If any of the parameters are not recognized, a
syntax error message will be displayed.
2. After the command is successfully parsed and validated, the control of execution
goes to the corresponding CLI callback function.
3. For mandatory parameters, the command tree extends until the mandatory param-
eters make the leaf of the branch. The callback function is only invoked when all
the mandatory parameters are provided. For optional parameters, the command
tree extends till the mandatory parameters and the optional parameters make the
leaf of the branch. However, the callback function is associated with the node
where the mandatory parameters are fetched. The callback function then takes
care of the optional parameters.
4. Once the control has reached the callback function, the callback function has
complete information about the parameters entered.
Note: Before Release 2.3, the VLAN mode was accessed from the Privileged Exec
mode. With Release 2.3, the mode is accessed from the Global Config mode by
entering the command interface vlan vlanid.