> On Jan 12, 2022, at 6:59 AM, Calvin DeBoer <calvin.deb...@toptal.com.invalid>
> wrote:
>
>
> Hello all, I'm struggling with understanding something in the error.log and
> could use some pointers on how to troubleshoot this. I've inherited a web app
> that uses apache as the webserver and is also using user apache user auth.
>
> Occasionally, Apache will just restart itself and it seems to take a while
> (Figure 0). I've ruled out usual suspects like memory, disk or processing
> capacity (this Ubuntu instance is on an ec2 instance with some very good
> specs, and the resource graphs have never even been close to high). Server
> and version details are in Figure 2 below.
>
> I'm trying to determine the root cause of this behavior. One culprit, based
> on some Stack reading, was possibly a reload/restart of Apache anytime the
> logs rotate. I've read that it's supposed to be a graceful restart, but
> perhaps something is causing the reload in the logrotate file to be
> ungraceful.
>
> I started grokking the error logs more carefully and spotted some error
> messages (Figure 1). I'm not sure what these mean, and their timestamps don't
> necessarily perfectly correlate to the restart / bad user experience
> (unresponsive web app).
>
> Does anyone here have any suggestions on where I can learn some more about
> the errors in Figure 1, or perhaps on additional log or config files I could
> be examining ?
>
> Figure 0 - Restart ? (error.log)
> [Wed Jan 12 00:00:08.735348 2022] [mpm_event:notice] [pid 14569:tid
> 139723494018368] AH00489: Apache/2.4.52 (Ubuntu) OpenSSL/1.1.1f configured --
> resuming normal operations
>
> Figure 1 - Error Entry (error.log)
> [Wed Jan 12 09:28:57.459259 2022] [session:error] [pid 25478:tid
> 139722760365824] (20014)Internal error (specific information not available):
> [client 172.70.230.157:44264] AH01816: error while loading the session,
> session not loaded: /socket.io/
> [Wed Jan 12 09:28:57.459224 2022] [session_dbd:error] [pid 25478:tid
> 139722760365824] [client 172.70.230.157:44264] AH01854: query execution error
> saving session 'd2866875-f3d3-475b-a523-aa34e2ee5351' in database using query
> 'selectsession':
>
> Figure 2 - Server/Apache Details (apache2 -v)
> Server version: Apache/2.4.52 (Ubuntu)
> Server built: 2021-12-28T20:18:12
> Ubuntu version: 18.04 LTS
looks like the trouble is in figure 1 a session dbd error indicates a database
problem.
[Wed Jan 12 09:28:57.459224 2022] [session_dbd:error] [pid 25478:tid
139722760365824] [client
