So my friends and I have been running our own Mattermost server for a couple weeks now without issue. Then out of nowhere, at 15:49 the server crashed/stopped. I’m running Mattermost 3.9.0 on Ubuntu 16.04, and I’ve included the only relevant log info I could find in syslog; as the mattermost log simply said “Stopping Mattermost”. As you can see, the whole thing seems to be correlated with the first log entry of “Starting Daily apt activities”. Any suggestions as to how to prevent this from occurring again? Thanks!
Jul 20 15:48:55 server1 systemd[1]: Starting Daily apt activities...
Jul 20 15:49:27 server1 systemd[1]: Reloading.
Jul 20 15:49:27 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:27 server1 systemd[1]: Stopping Mattermost...
Jul 20 15:49:27 server1 platform[8398]: [2017/07/20 15:49:27 CDT] [INFO] Stopping Server...
Jul 20 15:49:27 server1 platform[8398]: [2017/07/20 15:49:27 CDT] [INFO] Closing SqlStore
Jul 20 15:49:27 server1 platform[8398]: [2017/07/20 15:49:27 CDT] [INFO] stopping websocket hub connections
Jul 20 15:49:27 server1 platform[8398]: [2017/07/20 15:49:27 CDT] [INFO] Server stopped
Jul 20 15:49:27 server1 platform[8398]: 2017/07/20 15:49:27 http: response.WriteHeader on hijacked connection
Jul 20 15:49:27 server1 platform[8398]: 2017/07/20 15:49:27 runtime error: integer divide by zero
Jul 20 15:49:27 server1 systemd[1]: Stopped Mattermost.
Jul 20 15:49:27 server1 systemd[1]: Stopping MySQL Community Server...
Jul 20 15:49:29 server1 systemd[1]: Stopped MySQL Community Server.
Jul 20 15:49:29 server1 systemd[1]: Reloading.
Jul 20 15:49:29 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:29 server1 systemd[1]: Stopped MySQL Community Server.
Jul 20 15:49:30 server1 systemd[1]: Reloading.
Jul 20 15:49:30 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:32 server1 systemd[1]: Reloading.
Jul 20 15:49:32 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:33 server1 systemd[1]: Reloading.
Jul 20 15:49:33 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:33 server1 systemd[1]: Stopped MySQL Community Server.
Jul 20 15:49:33 server1 kernel: [3456696.879083] audit: type=1400 audit(1500583773.610:44): apparmor="STATUS" operation="profile_replace" profile="unconfin$
Jul 20 15:49:33 server1 kernel: [3456696.919040] audit: type=1400 audit(1500583773.650:45): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:33 server1 kernel: [3456696.919086] audit: type=1400 audit(1500583773.650:46): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:33 server1 kernel: [3456696.919157] audit: type=1400 audit(1500583773.650:47): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:33 server1 kernel: [3456697.095348] audit: type=1400 audit(1500583773.826:48): apparmor="STATUS" operation="profile_replace" profile="unconfin$
Jul 20 15:49:34 server1 systemd[1]: Reloading.
Jul 20 15:49:34 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:34 server1 systemd[1]: Reloading.
Jul 20 15:49:34 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:34 server1 systemd[1]: Starting MySQL Community Server...
Jul 20 15:49:34 server1 kernel: [3456697.582936] audit: type=1400 audit(1500583774.314:49): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:34 server1 kernel: [3456697.582983] audit: type=1400 audit(1500583774.314:50): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:34 server1 kernel: [3456697.583051] audit: type=1400 audit(1500583774.314:51): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:35 server1 systemd[1]: Started MySQL Community Server.
Jul 20 15:49:37 server1 systemd[1]: Reloading.
Jul 20 15:49:37 server1 systemd[1]: Started ACPI event daemon.
Jul 20 15:49:37 server1 systemd[1]: Stopping MySQL Community Server...
Jul 20 15:49:39 server1 systemd[1]: Stopped MySQL Community Server.
Jul 20 15:49:39 server1 systemd[1]: Starting MySQL Community Server...
Jul 20 15:49:39 server1 kernel: [3456702.723501] audit: type=1400 audit(1500583779.454:52): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:39 server1 kernel: [3456702.723548] audit: type=1400 audit(1500583779.454:53): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:39 server1 kernel: [3456702.723638] audit: type=1400 audit(1500583779.454:54): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" n$
Jul 20 15:49:40 server1 systemd[1]: Started MySQL Community Server.
Jul 20 15:49:47 server1 systemd[1]: Started Daily apt activities.
Jul 20 15:49:47 server1 systemd[1]: apt-daily.timer: Adding 3h 53min 14.035635s random time.
Jul 20 15:49:47 server1 systemd[1]: apt-daily.timer: Adding 9h 3min 44.540383s random time.