[bash] get user unknown ip from maillog
 

hi guys can u help here..
i can't find a command or any bash script to get ip for User unknown in my maillog file.

I had try to grep that line contain User unknown tag like this :

grep '[.][.][.] User unknown' maillog

but unfornately the ip was not in the line. Realized that the ip state one line after that.

Somebody please help..

man grep; grep -A, -C

thanks digiot!!
no reason to preasure out till forgot the man page :-lol :p

anyway this is my edit command to get the ip :

grep -A 1 '[.][.][.] User unknown' maillog | egrep -o -e "[0-9]{2,3}\.[0-9]{2,3}\.[0-9]{2,3}\.[0-9]{2,3}"