I’m using MailCow on a Ubuntu 2204 VM, running on a Synology DS 920+, for some time now, and I’m usually happy and find my way around (also thanks to this great community)… until I ran into the following problem this morning: the Dovecot container stopped, probably triggered by Watchdog, since all the other containers stopped as well.
The log shows:
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:01.634938320Z 2023-10-06 04:00:01,579 WARN received SIGTERM indicating exit request
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:01.748452680Z 2023-10-06 04:00:01,661 INFO waiting for processes, dovecot, syslog-ng to die
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:01.748516194Z Oct 6 04:00:01 65901a56010a syslog-ng: syslog-ng shutting down; version='3.28.1'
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:01.916570784Z 2023-10-06 04:00:01,892 INFO stopped: syslog-ng (exit status 0)
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:03.220295971Z 2023-10-06 04:00:03,219 WARN received SIGQUIT indicating exit request
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:03.332303127Z 2023-10-06 04:00:03,330 INFO stopped: dovecot (exit status 0)
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:03.332442180Z 2023-10-06 04:00:03,331 INFO reaped unknown pid 127 (exit status 0)
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T02:00:03.380773089Z 2023-10-06 04:00:03,373 INFO stopped: processes (terminated by SIGTERM)
The container then remained stopped until I started it manually this morning without issues, it is working fine since then:
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:37.082443505Z Uptime: 14160 Threads: 13 Questions: 19609 Slow queries: 0 Opens: 63 Open tables: 54 Queries per second avg: 1.384vmail’ is already a member of
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:38.563639985Z The user
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:39.120033501Z % Total % Received % Xferd Average Speed Time Time Time Current
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:39.121424397Z Dload Upload Total Spent Left Speed
100 112k 100 112k 0 0 513k 0 --:--:-- --:--:-- --:--:-- 513k
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:39.369412501Z 20_blatspammer.cf
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:39.369582748Z 70_HS_body.cf
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:39.372495628Z 70_HS_header.cf
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:40.037083765Z 2023-10-06 07:56:40,036 INFO Set uid to user 0 succeeded
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:40.047497739Z 2023-10-06 07:56:40,045 INFO supervisord started with pid 1
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:41.062878900Z 2023-10-06 07:56:41,049 INFO spawned: 'processes' with pid 117
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:41.062940148Z 2023-10-06 07:56:41,054 INFO spawned: 'dovecot' with pid 118
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:41.071614843Z 2023-10-06 07:56:41,068 INFO spawned: 'syslog-ng' with pid 119
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:41.243220478Z [2023-10-06T07:56:41.242412] WARNING: With use-dns(no), dns-cache() will be forced to 'no' too!;
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:41.247488372Z Oct 6 07:56:41 65901a56010a syslog-ng: syslog-ng starting up; version='3.28.1'
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:41.812114744Z Oct 6 07:56:41 65901a56010a dovecot: doveadm(firstname.lastname@example.org): Error: User doesn't exist
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:42.814420462Z 2023-10-06 07:56:42,813 INFO success: processes entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:42.814466043Z 2023-10-06 07:56:42,814 INFO success: dovecot entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
mailcowdockerized-dovecot-mailcow-1 | 2023-10-06T05:56:42.814479736Z 2023-10-06 07:56:42,814 INFO success: syslog-ng entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
When I read through the logs of this morning, I see some postfix issues, which seemingly resolved themselves, since the postfix container was up and running.
I attached the log as of today 04h - 05h local time.
The only thing happened around this time was the nighty renewal of my external IPv4/v6 addresses of my DSL connection.
It’s not too big of a deal to restart the container… if I’m at home (which often is not the case). So I would like to understand why the container didn’t come back up, i.e. where / in which log files can I find the root cause. Or how to avoid this issue altogether - can I safely disable watchdog in the conf file and run any system updates manually ?
Many thanks for your support and best regards,