Apache Rotate Logs and Log Rotate.

[David Robillard]

On 3/5/07, Peter Pluta <peter at placidpublishing.net> wrote:
> Gotcha, do you use a script to compress the logs after the SIGUSR1 and
> after waiting for a bit for apache to clear it's logging buffer (to not
> have missing logs)?

No I don't. I don't even see why one would want to do this?

Newsyslog deletes extra logs. So if our disk space is enough to hold
the amount of logs we require (see math below), then there's no need
to compress any Apache logs at all. Right!?!!

If we come back to my example of 100 VirtualHost with log files of 2Mb
each and we keep only 10 of them. Using USR1 as the kill signal, For
an httpd children to miss any log entry would mean that this children
writes more than 10 times 2Mb of logs in a very short period of time.
Check your VirtualHost load and determine the average response time
for each httpd children. If it's 2min (which is HUGE for an httpd
children) That would mean that you'd need to have more than 20Mb of
logs generated in less than 2min. In ASCII, that's a whole lot of
logs. I'd say your best bet would be to switch your LogLevel from
"debug" to "info" in your httpd.conf and restart Apache... ;)

Or you run a really busy website.
Or your web application code/architecture may need a revision.

Have fun!

David

> > Well, if you do use newsyslog to rotate Apache log files, then it's
> > just a matter of setting the number of files you whish to keep. From
> > newsyslog.conf(5)
> >
> >  count   Specify the maximum number of archive files which may exist.
> >          This does not consider the current log file.
> >
> > Let's say you rotate your files once they reach 2Mb for example and
> > that you've configured 10 in your newsyslog,conf <count> field. Then
> > that means a maximum of 10 x 2Mb = 20Mb will be kept for one
> > VirtualHost. Now if you have 100 virtual hosts all configured this
> > way, then you will need 100 x 20Mb = 2000Mb or 2Gb for all your Apache
> > logs.
> >
> > Considering today's disk drive sizes are well beyond the 300Gb, I
> > don't think this is a problem at all.
> >
> > Of course, YMMV so check your own needs and do the math.
> >
> > Cheers,
> >
> > David

-- 
David Robillard
UNIX systems administrator & Oracle DBA
CISSP, RHCE & Sun Certified Security Administrator
Montreal: +1 514 966 0122