Cisco switch cheatsheet

As the owner of a clunky ol' Cisco Catalyst 2950, and as a DEFINITELY NOT net admin, I decided to fiddle a bit more, both as a way to learn about networking (and cisco-based management) and as a way to optimize my current home network. Since the interface has some "strange" (to me) naming conventions and choices, I chose to document "usual" operations here, for later reference.

Quick tip: At any given time, press ? to get a list of what can be done using the current command prefix (what subcommands and such are available).

Global and hardware configuration setup

The 2950 has 24 100Mbit ports and a serial port (among other things). By default on a clean setup, the switch has the following configuration bits (nonexhaustive).

To reset the switch, the usual method is to press the front-left MODE button, then power the switch while maintaining the button press. After a few seconds, the LEDs will start to blink, and the SYST LED will be orange-colored. That means the flashing will be in progress.

Admin tasks

Once logged in, to su to gain elevated privileges, the enable command is used.

Password management

The command enable secret allows to set the password of enable. However, type 5 and 7 secrets are broken, and shouldn't be used if possible (replaced by type 8 and 9 if available).

Security issues & demo of type 5 and 7 secrets

Setting the base network configuration

Keeping this "automatic VLan mode", there are some things I choose to do.

hostname {hostname}
interface Vlan1
	ip address {ip} {mask}
	no ip route-cache
	no shutdown
!
ip default-gateway {router ip}
ip http server

In order, this is what is done.