Undoing running configuration

[cisco_lite]

What is the safest way to undo running configuration in cisco switches and routers.

[mlund]

Hi

I think there has been another thread about this, but I can't find it. However I copied a bit of it, and it is using the "config replace" and "archive" commands.

example

! this is better than "reload in 2"

r#show archive

There ara currently 4 archive configurations saved.

The next archive file will be named disk0:/config-archive-4

Archive # Name

0

1 disk0:/config-archive-1

2 disk0:/config-archive-2

3 disk0:/config-archive-3 <- Most recent

r#config replace disk00:/config-archive-3 time 120

:

... config changes are made

:

... your config change work OK

:

r#no config replace disk0:config-archive-3

here is a link describing it.

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t7/feature/guide/gtrollbk.html

/Mikael

[cisco_lite]

In the given link, it is mentioned

'When using the configure replace command, you must specify a saved Cisco IOS configuration as the replacement configuration file for the current running configuration'

Should a configure replace be followed by copy run start.

[mlund]

That depends of what you are trying to achive.

If the replaced config is not the same as in the startup-config, if a reload then occurs (by reload or by power-outage) then the stratup-config will be in place, and the replaced config will be lost.

If the replaced config is the one You want to be active even after a reboot, then a copy run start will be the right thing to do.

/Mikael