Quick question about using kill -USR1 to recreate access.log

[Francis Daly]

On Mon, May 19, 2014 at 03:06:06PM -0400, samingrassia wrote:

Hi there,

> mv $NGINX_ACCESS_LOG $ACCESS_LOG_DROPBOX/$LOG_FILENAME
> kill -USR1 `cat $NGINX_PID`
> 
> My questions is during time between the mv and the kill, is there any log
> writes that are being discarded or are they being stacked in memory and
> dumped into the new access.log after it is recreated?

What happens when you do

  mv $NGINX_ACCESS_LOG $ACCESS_LOG_DROPBOX/$LOG_FILENAME

and then issue a http request of your nginx server, before the kill?

Do you see the log line go into $NGINX_ACCESS_LOG; onto the end of
$ACCESS_LOG_DROPBOX/$LOG_FILENAME; or disappear without being written
anywhere?

I'd expect the first option not to happen; the second option to happen
if the "mv" is a "rename"; and the third option to happen if the "mv"
is a "copy and delete". So make sure that your "mv" is a "rename",
and you'll be fine.

Actually, I'd expect the first option to happen if you are using variables
in your log file name, according to its documentation.

	f
-- 
Francis Daly        francis at daoine.org