Need some help reading part of a log file...

[agangsto]

Hello.

I have a problem with reading a log file the way I want to.

I have many systems reporting errors to a file called "error.log" in a "main" system.
Only two of the systems in the file concerns me. (sys1 and sys2.)
To read the messages for the two systems I use the command:

tail -f error.log | egrep 'sys1'|'sys2'

This gives me only the information about sys1 and sys2.
However, this also gives me more information than I'd like.
Example of information given:
sys1 cooling warning
sys2 door open
sys2 cooling error
sys1 lost connection with hhut1
sys1 gained connection with hhut1
sys2 door closed

Lets say I want to exclude the information about cooling and door. My idea was to use this command:

tail -f error.log | egrep 'sys1|sys2' | egrep -v 'cooling|door'

My guess is that you know this does not work. I also guess that you know why.

Any one that care to help me out?

[raul.j]

Have you tried using sed:

tail -f error.log | sed -nr '/door|cooling/ d ; /sys1|sys2/ p'

Or try to flush the output from grep to let it pass through the second pipe:

error.log | grep -E --line-buffered 'sys1|sys2' | grep -E -v 'cooling|door'

[agangsto]

This works:

tail -f error.log | sed -nr '/door|cooling/ d ; /sys1|sys2/ p'

This does NOT work: (not for me anyway)

tail -f error.log | grep -E --line-buffered 'sys1|sys2' | grep -E -v 'cooling|door'

Thanks.