grep for ERROR in a folder full of logs...

ampapa · 09-23-2016, 08:42 AM

I have a folder full of logs that I would like to grep for the word 'ERROR' in. Is it possible to get output of the line containing the word along with the log that the word is in?

I'm a bit of a novice in Linux and just trying to get some help with the abundance of logs and how to manage them and review for errors, etc. Possibly get some notification when the word 'ERROR' comes up in a log...

Thanks for any suggestions.

ampapa,

syg00 · 09-23-2016, 09:03 AM

Have you read the manpage ?.

ampapa · 09-23-2016, 10:29 AM

Yes, somewhat but I guess I was looking for more insight into how others address logging and anticipating errors or system problems in more of a real time situation.

grep -l ERROR * , will list the log files with the ERROR but not the specific lines containing the errors. How would I be able to get a real time list if an error were occurring...

ampapa,

Habitual · 09-23-2016, 12:02 PM

basic shotgun grep

Code:

grep -w <whole_word> /path/to/search/* -R

excess output, you say?
Show just the files where hits occur:

Code:

grep -w <whole_word> /path/to/search/* -Rl

Level Up:

Code:

find /path/to/search -type f -exec grep -w <whole_word> {} \;

Have fun.

pan64 · 09-23-2016, 12:22 PM

Quote:

Originally Posted by ampapa

grep -l ERROR * , will list the log files with the ERROR but not the specific lines containing the errors. How would I be able to get a real time list if an error were occurring...

These are two different things

Code:

grep -n -H <pattern> -R <dir>

can be used the find lines containing the pattern.
But real time list is another issue, cannot be solved just with a grep. And I think you do not really want that.

ampapa · 09-23-2016, 01:04 PM

Thanks.

I was looking at LogStash as a more robust option, anyone have any experience with it or can make another open source suggestion?

chrism01 · 09-30-2016, 12:23 AM

If you wanted to grab an error msg as it occurred, you'd want to prefix the above cmds like 'tail -f <file> |grep ...' .
I've used that interactively.

If you want a programmatic soln I've successfully used Perl with http://search.cpan.org/~mgrabnar/File-Tail-1.3/Tail.pm

c0wb0y · 09-30-2016, 12:46 AM

Try this:

Code:

grep -n ERROR $(grep -l ERROR *)

ampapa · 10-21-2016, 10:51 AM

Habitual,

This gets me closer to a solution that would work for me.

Code:

grep -w <whole_word> /path/to/search/* -Rl

Is it also possible to only search .log files and list line with the error?

Ampapa,

Habitual · 10-21-2016, 11:13 AM

Quote:

Originally Posted by ampapa

Habitual,

This gets me closer to a solution that would work for me.

Code:

grep -w <whole_word> /path/to/search/* -Rl

Is it also possible to only search .log files and list line with the error?

Ampapa,

Sure, try

Code:

grep -w <whole_word> /path/to/search/*.log -Rln

Have fun!
Using the find utility is the next logical step...

Code:

find <path> -type f -iname '*.log' -exec grep <stuff>

szboardstretcher · 10-21-2016, 11:15 AM

Something like:

Code:

grep -nH <whole_word> /path/to/search/*.log -Rl

ampapa · 10-21-2016, 01:28 PM

Quote:

Originally Posted by Habitual

Sure, try

Code:

grep -w <whole_word> /path/to/search/*.log -Rln

[/CODE]

Thanks, that got me close enough...

Quote:

-R, -r, --recursive equivalent to --directories=recurse
--include=FILE_PATTERN search only files that match FILE_PATTERN

This worked...

Code:

grep -w <whole_word> /path/to/search/* --include=.log -Rln

Last follow up.. is it possible to also search by line date/time in the file? It would be nice to hone in on current ERROR's...

Habitual · 10-21-2016, 01:44 PM

Quote:

Originally Posted by ampapa

Thanks, that got me close enough...

This worked...

Code:

grep -w <whole_word> /path/to/search/* --include=.log -Rln

Last follow up.. is it possible to also search by line date/time in the file? It would be nice to hone in on current ERROR's...

Yes it is possible.
See https://www.digitalocean.com/communi...-text-in-linux

and ask if you have any further Qs, and show some of your work.