Wednesday, March 2, 2011

Rolling Back Your Configurations

We've all had to bear the pain of having to erase the startup-config and reload to get a fresh, out of the box configuration on a Cisco router or switch.  Once you caught on to the patterns in the lab guides, you probably even saved your configurations after you typed in the base configs and then reloaded to return to that point.  Even then, reloading is a process that takes time.  If you're impatient like me, it's too much time. 

Well, there is a command to revert you back to your last save point almost immediately.  It is as follows:

R1#config replace nvram:startup-config force

As stated, this command will almost instantly boot up the startup-config (aka the last time you performed a copy run start or wr command).  If you saved it immediately after your basic configs, this command will wipe out everything but those in a matter of seconds.

If you wanted to save even more time, alias the command.

R1(config)#alias exec rr config replace nvram:startup-config force

This command ties the "config replace" command to "rr".  You can use any letter combo instead of "rr".  That's just what I use.  I'll cover alias commands in another blog.

So now, to instantly revert back to the last save point:

R1# rr

Total number of passes: 1
Rollback Done


Enjoy!!