LFU 13: Know Your Defaults

If you reverse out something, make sure that it’s not a default.

I accidentally configured “logging monitor”.  No problem, I’ll just remove the command with “no logging monitor”.  No problem…except that “logging monitor” is a default command. 

r3(config)#logging mon
r3(config)#no logg mon
r3(config)#do sh run | i logg
no logging monitor   <-oops!!!!
logging trap debugging

By not knowing that “logging monitor” is on by default, I just changed the configuration of my router and I could lose points when the lab is graded.

If you accidentally turn on a function, do a quick “show run | i [function]”.  If it does not show up, then it is a default and you can go on your merry way.  If it does show up, then you will need to back it out.