What is your favorite DEBUG command?

Node Man

Hi Everybody,
What is your favorite, or most used, or most useful, debug command?

Im going with: DEBUG IP OSPF AUTHEN

Just wondering.

networker050184

It depends on what I'm doing really. The most useful debugs I've used are for tracing calls though. Probably 'debug isdn q931' for analog calls and 'debug ccsip messages' for SIP legs.

theodoxa

I wish there was a way to filter debug messages by severity (Notice, Warning, Error) like servers do, or maybe I just don't know how. I didn't know you could filter them with ACLs (by port, protocol, etc...) until I saw it done in an INE Video. That said, I would have to go with:

debug ip ospf adj
debug ip eigrp neigh

I will sometimes turn these on before entering Network commands. If the commands are entered correctly, I will get the relevant debug messages indicating a new adjacency or neighbor relationship.

MrXpert

There's loads of good ones but for OSPF i'd use debug ip ospf packet. BGP: debug ip bgp. EIGRP:debug eigrp packet terse. Other useful ones are debug ip routing, debug ip ospf hello,debug standby terse, debug ip packet (the one where you can specify an ACL to match against)

prtech

debug all

j/k

"debug ip ospf adj" is the only one I've ever used and that was in a lab we use for interviews.

instant000

"undebug all" is the most useful one to me.

When facing a wall of text, it's usually shortened to "un all" or some other short-hand variant.