Basic Operations #

Navigate Between IOS Modes #

Move between User EXEC mode and Privileged EXEC mode
```
Switch> enable
Switch# disable
Switch>
```
Move between Privileged EXEC mode and Global Configuration mode
```
Switch# configure terminal
Switch(config)# exit
Switch#
```

Move from any sub-configuration mode to Privileged EXEC mode

Switch(config-line)# end
Switch#
% or
Switch(config-line)# <Ctrl+Z>
Switch#

Use the do command to run User EXEC mode commands whlie in EXEC mode
```
Switch(config)# do show running-config
```

Commands Shortening #

Commands and keywords can be shortened to the minimum number of characters that identify a unique selection.

Switch# conf t
Switch(config)#

Switch# con t
% Ambiguous command: “con t”

Keyboard Shortcuts #

Shortcut	Description
?	List available commands.
Tab	Autocomplete & check if the current command is viable.
Ctrl + Z	Return to Privileged EXEC Mode.
Ctrl + Shift + 6	Cancel Cisco IOS process.
Up Arrow / Down Arrow	Scroll through previously entered commands.

Device Configuration #

Configure Hostname #

Switch# configure terminal
Switch(config)# hostname <hostname>
<hostname>(config)#

Configure Password #

Console Access password

Switch(config)# line console 0
Switch(config-line)# password <password>
Switch(config-line)# login
Switch(config-line)# exit
Switch(config)#

Privileged EXEC Access password

Switch(config)# enable password <password>

Configure Users and their Secrets #

Console Access secret

Switch(config)# username <user> secret <password>
Switch(config)# line console 0
Switch(config-line)# login local
Switch(config-line)# exit
Switch(config)#

Privileged EXEC Access secret

Switch(config)# enable secret <password>

Configure a Range of Interfaces #

Switch(config)# interface range GigabitEthernet0/<start>-<end>

Delete Specific Configuration #

Switch(config)# interface <interface>
Switch(config-if)# no <configuration_command>

Banner Message Configuration #

The delimiter can be any character, being used to mark the start and end of message.

Switch(config)# banner motd !
<message>
!
Switch(config)#

SSH Configuration #

Configure hostname and domain name

Switch(config)# hostname <hostname>
Switch(config)# ip domain-name <domain_name>

Configure RSA key pair

Switch(config)# crypto key generate rsa
! Choose modulus length = 1024

Choose SSH version
```
Switch(config)# ip ssh version 2
```

Allow users to login by SSH

Switch(config)# line vty 0 15
Switch(config-line)# transport input ssh
Switch(config-line)# login local

Save the Configuration File #

To save the running configuration to the startup configuration, use one of the following commands.

Switch# copy running-config startup-config
% or
Switch# write memory

Verify and Monitor Cisco Device #

Switch# show running-config
Switch# show startup-config
Switch# show interfaces
Switch# show arp
Switch# show version

Network Discovery #

Cisco Discovery Protocol #

Show all CDP neighbors
```
Switch# show cdp neighbors
```
Show details of one neighbor
```
Switch# show cdp entry <device_id>
```
Disable CDP globally
```
Switch(config)# no cdp run
```

Disable CDP for an interface

Switch(config)# interface <interface>
Switch(config-if)# no cdp enable

Link Layer Discovery Protocol #

Enable LLDP globally
```
Switch(config)# lldp run
```

Enable LLDP for an interface

Switch(config)# interface <interface>
Switch(config-if)# lldp receive
Switch(config-if)# lldp transmit

Show all LLDP neighbors
```
Switch# show lldp neighbors
```

Device Management and Security #

Shut Down Unused Ports #

Identify unused ports
```
Switch# show interfaces status
```

Shut down unused ports

Switch(config)# interface <interface>
Switch(config-if)# shutdown

Force Other Users to Logout #

Check current connections

Switch# show users

   Line    User   Host(s)  Idle      Location
* 0 con 0         idle     00:00:00
  2 vty 0  user2  idle     00:00:45
  3 vty 1  user3  idle     00:00:23

Disconnect a user session by clearing a VTY line
```
Switch# clear line vty <line_num>
```

Password Recovery #

Initialize the flash file system

The system has been interrupted ...

switch: flash_init

Display the contents of the flash memory

switch: dir flash:

Directory of flash:/
  13  drwx  192   Mar 01 1993 22:30:48  c2960-lanbase-mz.122-25.FX
  11  -rwx  5825  Mar 01 1993 22:31:59  config.text
  18  -rwx  720   Mar 01 1993 02:21:30  vlan.dat

Rename config.text

switch: rename flash:config.text flash:config.bak

Boot the system
```
switch: boot
```

Skip the initial configuration dialog

In order to access the device manager, ...
[...]
Would you like to enter the initial configuration dialog?

[yes/no]: no

Restore the configuration file and running-config

Switch> enable
Switch# copy running-config startup-config
Switch# copy flash:config.bak flash:config.text
Switch# copy startup-config running-config

Update the console password

Switch(config)# line console 0
Switch(config-line)# password passwd
Switch(config-line)# login

Save the configuration to startup-config

Switch# copy running-config startup-config

Reset the Switch #