How can I fix "/etc/cron.daily/logrotate: gzip: stdin: file size changed while zipping"?

Question

in last days i get daily mail from cron's logrotate task:

/etc/cron.daily/logrotate:

gzip: stdin: file size changed while zipping

How can I fix it?

Thanks, Gian Marco.

See [here](http://superuser.com/questions/630782/) – Jérôme Jul 20 '15 at 07:52 — Jérôme, Jul 20 '15 at 07:52

lamanux · Answer 1 · 2019-06-24T16:18:23.653

26

Here's a blog post in French which gives a solution.

In English, you can read this bug report.

To summarise:

First you have to add the --verbose option in the script /etc/cron.daily/logrotate to have more information the next time it runs to identify which rotation log cause the problem.
```
#!/bin/sh

test -x /usr/sbin/logrotate || exit 0
/usr/sbin/logrotate --verbose /etc/logrotate.conf`
```

Next you have to add the delaycompress option in logrotate configuration.

Like exemple, I add the nginx's logrotate configiguration in /etc/logrotate.d/nginx:

/var/log/nginx/*.log {
    daily
    missingok
    rotate 14
    compress
    delaycompress
    notifempty
    create 0640 www-data adm
    sharedscripts
    ...
}

edited Jun 24 '19 at 16:18

answered Aug 17 '15 at 08:25

lamanux

551
4
11

1

Can you run the logrotate straight away or do you have to wait for it to run again? How do you add delaycompress to the logrotate configuration? Can you give an example? – Lance Jun 27 '16 at 08:31
2

@LanceHolland you can run it again with: /usr/sbin/logrotate /etc/logrotate.conf However, depending on your logrotate settings (frequency, minsize, etc), the conditions may not be sufficient to cause the gzip issue. I think it is best to add verbose and then let it run as per the daily schedule. – Joe Niland Jul 01 '16 at 01:13
`delaycompress` will only help you in certain cases. See my answer. – Ztyx Jan 09 '17 at 14:35

score 4 · Answer 2 · edited May 07 '18 at 06:34

upstart will close (and reopen) its log file when it notices that the file is deleted. However, if you look at what gzip does, you see that it doesn't delete the file until after it's one writing the output file. That means that there always is a race condition where log lines might be lost for lines logs being written gzipping.

You can disable the warning using gzip --quiet, but really that doesn't hide the fact that you might still loose log lines.

This means that delaycompress is not a generic fix to this. It's a specific fix to a specific problem.

The real solution for this is probably a combination of delaycompress and being able to send a signal to the process. It will make the race condition go away in practise (unless you rotate multiple times per second :) ).

How can I fix "/etc/cron.daily/logrotate: gzip: stdin: file size changed while zipping"?

2 Answers2