CCNA COMMAND

Command		descriptions
switch>?		The ? works here the same as in a router Used to get the list of all available commands
switch>enable		User mode, same as a router
switch#		Privileged mode
switch#disable		Leaves privileged mode
switch>exit		Leaves user mode
switch#show version		Displays information about software and hardware.
switch#show flash:		Displays information about flash memory (will work only for the 2900/2950 series).
switch#show mac-address-table		Displays the current MAC address forwarding table .
switch#show running-config		Displays the current configuration in DRAM.
switch#show startup-config		Displays the current configuration in NVRAM.
switch#show vlan		Displays the current VLAN configuration.
switch#show interfaces		Displays the interface configuration and status of line: up/up, up/down, admin down.
switch#show interface vlan1		Displays setting of virtual interface VLAN 1, the default VLAN on the switch.
To Reset Switch Configuration
Switch#delete flash:vlan.dat		Removes the VLAN database from flash memory.
Delete filename [vlan.dat]?		Press Enter
Delete flash:vlan.dat? [confirm]		Press Enter
Switch#erase startup-config		Erases the file from NVRAM.
Switch#reload		Restarts the switch.
To Set Host Names
Switch#configure terminal		Moves to global configuration mode
Switch(config)#hostname Switch1		Creates a locally significant host name of the switch. This is the same command as the router.
Switch1(config)#
To Set Passwords
Switch(config)#enable password vinita		Sets the enable password to vinita
Switch(config)#enable secret nikki		Sets the encrypted secret password to nikki
Switch(config)#line console 0		Enters line console mode
Switch(config-line)#login		Enables password checking
Switch(config-line)#password vinita		Sets the password to vinita
Switch(config-line)#exit		Exits line console mode
Switch(config-line)#line vty 0 4		Enters line vty mode for all five virtual ports
Switch(config-line)#login		Enables password checking
Switch(config-line)#password vinita		Sets the password to vinita
Switch(config-line)#exit		Exits line vty mode
Switch(config)#
To Set IP Addresses and Default Gateways
Switch(config)#interface vlan1		Enters the virtual interface for VLAN 1, the default VLAN on the switch
Switch(config-if)#ip address 192.168.0.10 255.255.255.0		Sets the IP address and netmask to allow for remote access to the switch
Switch(config-if)#exit
Switch(config)#ip default-gateway 192.168.0.5		Allows IP information an exit past the local network
To Set Interface Descriptions
Switch(config)#interface fastethernet 0/1		Enters interface configuration mode
Switch(config-if)#description Finance VLAN		Adds a description of the interface
To Set Duplex Operation
Switch(config)#interface fastethernet 0/1		Moves to interface configuration mode
Switch(config-if)#duplex full		Forces full-duplex operation
Switch(config-if)#duplex auto		Enables auto-duplex config
Switch(config-if)#duplex half		Forces half-duplex operation
To Set Operation Speed
Switch(config)#interface fastethernet 0/1
Switch(config-if)#speed 10		Forces 10-Mbps operation
Switch(config-if)#speed 100		Forces 100-Mbps operation
Switch(config-if)#speed auto		Enables autospeed configuration
MAC Address Table
switch#show mac address-table		Displays current MAC address forwarding table
switch#clear mac address-table		Deletes all entries from current MAC address forwarding table
switch#clear mac address-table dynamic		Deletes only dynamic entries from table
Switch(config)#vlan 10	Creates VLAN 10 and enters VLAN configuration mode for further definitions.
Switch(config-vlan)#name Sales	Assigns a name to the VLAN. The length of the name can be from 1 to 32 characters.
Switch(config-vlan)#exit	Applies changes, increases the revision number by 1, and returns to global configuration mode.
Switch(config)#interface fastethernet 0/1	Moves to interface configuration mode
Switch(config-if)#switchport mode access	Sets the port to access mode
Switch(config-if)#switchport access vlan 10	Assigns this port to VLAN 10
Switch#show vlan	Displays VLAN information
Switch#show vlan brief	Displays VLAN information in brief
Switch#show vlan id 10	Displays information about VLAN 10 only
Switch#show vlan name sales	Displays information about VLAN named sales only
Switch#show interfaces vlan x	Displays interface characteristics for the specified VLAN
Switch#delete flash:vlan.dat Delete filename [vlan.dat]? Delete flash:vlan.dat? [confirm] Switch#	Removes the entire VLAN database from flash. Make sure there is no space between the colon (:) and the characters vlan.dat. You can potentially erase the entire contents of the flash with this command if the syntax is not correct. Make sure you read the output from the switch. If you need to cancel, press ctrl+c to escape back to privileged mode:
Switch(config)#interface fastethernet 0/5	Moves to interface configuration mode.
Switch(config-if)#no switchport access vlan 5	Removes port from VLAN 5 and reassigns it to VLAN 1—the default VLAN.
Switch(config-if)#exit	Moves to global configuration mode.
Switch(config)#no vlan 5	Removes VLAN 5 from the VLAN database.
Switch#copy running-config startupconfig	Saves the configuration in NVRAM
Switch(config-if) #switchport mode trunk	Puts the interface into permanent trunking mode and negotiates to convert the link into a trunk link.
Switch(config)#vtp mode server	Changes the switch to VTP server mode.
Switch(config)#vtp mode client	Changes the switch to VTP client mode.
Switch(config)#vtp mode transparent	Changes the switch to VTP transparent mode.
Switch(config)#no vtp mode	Returns the switch to the default VTP server mode.
Switch(config)#vtp domain domain-name	Configures the VTP domain name. The name can be from 1 to 32 characters long.
Switch(config)#vtp password password	Configures a VTP password .
Switch(config)#vtp pruning	Enables VTP pruning
Switch#show vtp status	Displays general information about VTP configuration
Switch#show vtp counters	Displays the VTP counters for the switch