Shamefully taken from  https://www.eng.uwaterloo.ca/twiki/bin/view/Engcomp/CommonCiscoCommands

To enable privileged command mode

enable

To enter switch configuration mode (from privileged command mode)

configure terminal

To enter port configuration mode (from switch configuration mode)

interface FastEthernet0/5

To return from one mode to the previous mode

exit

To show the mac table

show mac-address-table

To show port information

show interfaces

To show the switch version

show version

To save the configuration

write memory

To show the configuration

show running-config

To set the port description of FastEthernet0/5 to “engmail”

configure terminal
interface FastEthernet0/5
description engmail
exit

To remove the port description from FastEthernet0/5

configure terminal
interface FastEthernet0/5
no description
exit

To set FastEthernet0/5 to 100/full

configure terminal
interface FastEthernet0/5
speed 100
duplex full
exit

To set FastEthernet0/5 to auto/auto

configure terminal
interface FastEthernet0/5
speed auto
duplex auto
exit

To turn FastEthernet0/5 into a dot1q trunk

configure terminal
interface FastEthernet0/5
no switchport access vlan
switchport mode trunk
switchport trunk encapsulation dot1q
exit

To turn FastEthernet0/5 into a non trunk

configure terminal
interface FastEthernet0/5
no switchport mode trunk
no switchport trunk encapsulation
no switchport trunk allowed vlan
no switchport trunk native vlan
switchport mode access
exit

To set the allowed vlans on trunk port FastEthernet0/5 to 20,50,100

configure terminal
interface FastEthernet0/5
switchport trunk allowed vlan 20,50,100
exit

To remove the allowed vlans from trunk port FastEthernet0/5 (will default to all vlans in vlan database)

configure terminal
interface FastEthernet0/5
no switchport trunk allowed vlan
exit

To restrict the number of mac address on FastEthernet0/5 to 1

2900/3500 series…

configure terminal
interface FastEthernet0/5
port security max-mac-count 1
exit

2950/3550 series…

conf term
interface FastEthernet0/5
switchport port-security
switchport port-security maximum 1
switchport port-security violation protect
switchport port-security mac-address sticky
switchport port-security aging static
exit

To remove the mac address restriction from FastEthernet0/5

configure terminal
interface FastEthernet0/5
no port security
exit

To set the vlan on FastEthernet0/5 to 150

configure terminal
interface FastEthernet0/5
switchport access vlan 150
exit

To remove the vlan from FastEthernet0/5 (port will default to vlan 1)

configure terminal
interface FastEthernet0/5
no switchport access vlan
exit

To set the native vlan (untagged vlan) on trunk FastEthernet0/5 to 75

configure terminal
interface FastEthernet0/5
switchport trunk native vlan 75
exit

To remove the native vlan (untagged vlan) from trunk FastEthernet0/5

configure terminal
interface FastEthernet0/5
no switchport trunk native vlan
exit

To set FastEthernet0/5 to portfast

configure terminal
interface FastEthernet0/5
spanning-tree portfast
exit

To set FastEthernet0/5 to not be portfast

configure terminal
interface FastEthernet0/5
no spanning-tree portfast
exit

To disable spanning tree on vlan 20

configure terminal
no span vlan 20
exit

To enable spanning tree on vlan 20

configure terminal
span vlan 20
exit

To disable port FastEthernet0/5

configure terminal
interface FastEthernet0/5
shutdown
exit

To enable port FastEthernet0/5

configure terminal
interface FastEthernet0/5
no shutdown
exit

To get a GBIC port to talk to a BayStack

configure terminal
interface GigabitEthernet0/2
no negotiation auto
exit

IOS upgrade (general procedure)

Important. Read the Cisco documentation. This procedure is minimal, and does not install the web management interface. Do not follow these instructions unless you are familliar with the procedure.

dir flash:

delete the html directory, and diag file (if any)

delete flash:html/*

rename the existing image to the name of the new image

rename flash:c3500XL-c3h2s-mz.120-5.WC2.bin flash:c3500xl-c3h2s-mz.120-5.WC5a.bin
conf term
boot system flash:c3500xl-c3h2s-mz.120-5.WC5a.bin
exit
copy tftp://129.97.x.y/tmpdata/c3500xl-c3h2s-mz.120-5.WC5a.bin flash:c3500xl-c3h2s-mz.120-5.WC5a.bin
copy flash:c3500xl-c3h2s-mz.120-5.WC5a.bin tftp://129.97.x.y/tmpdata/junk

check the md5 on junk compared to c3500xl-c3h2s-mz.120-5.WC5a.bin before doing the reload

write mem
reload