The Catalyst 1900 Switch

The Catalyst 1900 Switch can be configured by a menu system, the Command Line Interface (CLI) or the Virtual Switch Manager (VSM) through a web browser once the IP address has been set. By pressing K at the first menu, you can access the CLI. The switch can table up to 1024 MAC addresses. The 1900 can use Store-and-Forward or FragmentFree (default) switching modes.

enable/disable: used to enter or exit the privileged mode

General commands entered in the “#” mode:

show version: displays basic IOS and switch information.

show ip: used to see the IP address settings on the switch, along with subnet, default gateway, domain name, and other parameters.

ping address: used to test connectivity from the switch. telnet or traceroute can only be used from a router.

delete nvram/vtp: erases the startup-config of a switch or VTP information. You cannot see the content of the startup-config on a switch, nor copy to or from it. Every changes made to the configuration is made to the NVRAM file immediately.

sh mac-address-table: displays the MAC address table.

clear mac-address-table dynamic/permanent/restricted: clears the address in the MAC address table that match the option chosen.

sh port system: displays information about switching type. Fragment-Free is the default switching mode.

sh vlan [number]: displays the VLAN information and port association about all VLANs or only the number VLAN.

sh vlan-membership: displays the VLAN information for all the interfaces.

sh trunk a/b [allowed-vlans/joined-vlans/joining-vlans/prune-eligible]: displays trunk information (port 26=A, 27=B).

copy tftp://hostaddress/IOSfilename opcode: used to update the IOS on the switch from a tftp server.

copy nvram tftp://hostaddress/filename: used to backup the startup-config file.

copy tftp://hostaddress/filename nvram: used to restore the startup-config file.

show cdp: displays cdp information.

config terminal: use to enter the terminal configuration

Commands entered in the “(config)#” mode:

hostname name: used to define a hostname that is locally significant only.

enable password level number password: used to set user and enable mode passwords (by setting number to either 1 or 15 respectively). Password must be between 4 and 8 characters and is not case sensitive.

en secret password : used to set the enable password using the encryption service. This will override the non-secure password if set.

ip (address ipaddress subnetmask)/(default-gateway gatewayaddress): used to set the IP address and subnet mask, or the gateway.

mac-address-table aging-time time: sets the aging time of dynamic addresses in .

mac-address-table permanent address destinterface: used to define permanent addresses.

mac-address-table restricted static address destinterface sourceinterface: used to define restricted addresses.

switching-mode fragment-free/store-and-forward: used to set the switching mode.

vlan number name name: defines VLANs. number is 1-1000. VLAN 1 is the default VLAN and all ports are associated to it. Maximum of 64 VLANs on a switch.

vtp server/client/(domain name)/(password pw)/(pruning en/dis)/transparent/trap : configures VLAN Trunk Protocol . Pruning is enabled on the whole domain if it is enabled on a server.

cdp advertise-v2/(holdtime/timer seconds): used to configure CDP (Cisco Discovery Protocol) information.

interface (ethernet 0/1-25)/(fastethernet 0/26-27) : the Ethernet interfaces are numbered 1-24, plus the serial port for AUI at the back, and the FastEthernet uplink ports are numbered 26-27. There is only one slot, slot 0.

Commands entered in the “(config-if)#” or “(config-subif)#” mode:

duplex auto/full/full-flow-control/half : used to change the duplex settings on a given port. auto is the default for 100BaseTX ports, and half is the default for 10BaseTX ports.

description name: used to define a description for the interface. Name must have underscores rather than spaces. show run and show int 0/n will both show the descriptions set.

port secure max-mac-count number: will only allow number MAC addresses on the interface, and they will be permanent.

vlan-membership static/dynamic number: assigns a port to a VLAN. One VLAN per port unless trunking is used.

trunk auto/desirable/nonegotiate/on/off: used on the FastEthernet ports to enable trunking. All VLANs are allowed on the trunk by default.

no trunk-vlan number: to clear VLAN number from being trunked through this interface.

encapsulation isl vlan_number: in each subinterface of a trunk port, in order to support VLAN trunking.