6

We had sar working on our Ubuntu server, but did some work on the server and now it's stopped logging to the day's logfile.

sar -b 5 5

This indicates that sar is alive, and monitoring data, but

ubuntu@testing:/var/log/sysstat$ sar

outputs:

Linux 5.4.0-1063-azure (server)     02/22/22    _x86_64_    (4 CPU)

10:22:05     LINUX RESTART  (4 CPU)


10:22:46     LINUX RESTART  (4 CPU)


10:24:25     LINUX RESTART  (4 CPU)


16:34:04     LINUX RESTART  (4 CPU)

The cron and the sysstat config have not changed.

*/1 * * * * root command -v debian-sa1 > /dev/null && debian-sa1 1 1

Why isn't stats data getting added to the log?

strangerpixel
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2 Answers2

8

Comparing 2 installations, one is Debian 11 that was upgraded from Debian 10, and the other is a fresh Debian 11, both using systemd:

  • on Debian 10 then 11, I already have sysstat-collect and sysstat-summary enabled
  • on fresh Debian 11, I don't

So, if you're using systemd, you should reconfigure sysstat that will run through systemd and not through crontab:

dpkg-reconfigure sysstat

Select "Yes".

Editing /etc/default/sysstat directly (as I did until now) is a mistake: it doesn't update systemd files.

Note that you'll see /etc/default/sysstat updated to ENABLED="true", but the cron won't run anymore (systemd will trigger it as expected).

You can check everything is fine using:

systemctl status sysstat-collect.timer
systemctl status sysstat-summary.timer

which should reply with «Active: active (waiting)»

Yvan
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0

I had the same problem, and in my case (Debian 11), one solution was changing debian-sa1 to sa1 in the cron file since the debian-sa1 will be exited when the system is shipped with being systemd enable.

After applying this hack, the cron config file of sysstat would be like this (/etc/cron.d/sysstat):

...
*/1 * * * * root command -v sa1 > /dev/null && sa1 1 1
...

EDIT:

As Yvan explained, to run sysstat by systemd instead of cron, we can start sysstat-collect.timer and sysstat-summary.timer timers manually, in case they are inactive:

systemctl start sysstat sysstat-collect.timer sysstat-summary.timer

And also enable them to be automatically started by system boot-up:

systemctl enable sysstat sysstat-collect.timer sysstat-summary.timer

Finally and after explaining these hacks, maybe the best solution, in this case, is to reconfigure sysstat to be run with systemd instead of cron, which is greatly described in this answer by Yvan.

armanexplorer
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