Diff'ing Cisco IOS Startup-config and running-config

How many times have you needed to know what you are about to commit to your startup-config. The following should help you work out if you are storing what you think you are, or at least show you whats changed from your startup config.

show archive config differences

If there is nothing pending you will get something like

!Contextual Config Diffs:
!No changes were found

If changes are pending you will see them listed in a format similar to below.

!Contextual Config Diffs:
interface GigabitEthernet0/2
 +no ip address
 +shutdown
interface GigabitEthernet0/2
 -ip address 10.188.1.1 255.255.255.0
telephony-service
 -cnf-file location flash:
 -network-locale GB

Lines starting with a + are lines which are in the startup-config would be reinstated on reload. Lines starting with – are lines that are in the running-config and would be lost in a reload.