Any thoughts on how to debug this database problem ? Does apache2 maintain its own database for sessions etc, and does it have some instrumentation or logs I could examine ?
On Wed, Jan 12, 2022 at 10:45 PM Curtis Maurand <cur...@maurand.com> wrote: > > > > 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 > <https://unix.stackexchange.com/questions/47688/how-to-avoid-apache-reload-when-rotating-logs>, > 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 > > >
