I’ve just upgraded host CentOS to 8.2.2004 (released 2020-06-15) and after restart the PMM container reports unhealthy. The logs are:
# docker logs 6f91f53a5e74
2020-06-21 15:11:43,035 INFO Included extra file “/etc/supervisord.d/alertmanager.ini” during parsing
2020-06-21 15:11:43,035 INFO Included extra file “/etc/supervisord.d/pmm.ini” during parsing
2020-06-21 15:11:43,036 INFO Included extra file “/etc/supervisord.d/prometheus.ini” during parsing
2020-06-21 15:11:43,036 INFO Included extra file “/etc/supervisord.d/qan-api2.ini” during parsing
2020-06-21 15:11:43,036 INFO Set uid to user 0 succeeded
2020-06-21 15:11:43,045 INFO RPC interface ‘supervisor’ initialized
2020-06-21 15:11:43,045 INFO supervisord started with pid 1
2020-06-21 15:11:44,048 INFO spawned: ‘postgresql’ with pid 12
2020-06-21 15:11:44,051 INFO spawned: ‘clickhouse’ with pid 13
2020-06-21 15:11:44,053 INFO spawned: ‘grafana’ with pid 14
2020-06-21 15:11:44,054 INFO spawned: ‘nginx’ with pid 15
2020-06-21 15:11:44,055 INFO spawned: ‘cron’ with pid 16
2020-06-21 15:11:44,062 INFO spawned: ‘prometheus’ with pid 17
2020-06-21 15:11:44,064 INFO spawned: ‘alertmanager’ with pid 18
2020-06-21 15:11:44,066 INFO spawned: ‘dashboard-upgrade’ with pid 19
2020-06-21 15:11:44,068 INFO spawned: ‘qan-api2’ with pid 20
2020-06-21 15:11:44,070 INFO spawned: ‘pmm-managed’ with pid 21
2020-06-21 15:11:44,076 INFO spawned: ‘pmm-agent’ with pid 22
2020-06-21 15:11:44,181 INFO success: dashboard-upgrade entered RUNNING state, process has stayed up for > than 0 seconds (startsecs)
2020-06-21 15:11:44,211 INFO exited: qan-api2 (exit status 1; not expected)
2020-06-21 15:11:44,374 INFO exited: dashboard-upgrade (exit status 0; expected)
2020-06-21 15:11:45,538 INFO success: postgresql entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,538 INFO success: clickhouse entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,538 INFO success: grafana entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,538 INFO success: nginx entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,538 INFO success: cron entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,538 INFO success: prometheus entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,539 INFO success: alertmanager entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,539 INFO spawned: ‘qan-api2’ with pid 130
2020-06-21 15:11:45,540 INFO success: pmm-managed entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:45,540 INFO success: pmm-agent entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:46,648 INFO success: qan-api2 entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:49,121 INFO exited: nginx (exit status 1; not expected)
2020-06-21 15:11:49,122 INFO spawned: ‘nginx’ with pid 154
2020-06-21 15:11:50,323 INFO success: nginx entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:11:59,142 INFO exited: nginx (exit status 1; not expected)
2020-06-21 15:11:59,143 INFO spawned: ‘nginx’ with pid 180
2020-06-21 15:12:00,145 INFO success: nginx entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:12:09,158 INFO exited: nginx (exit status 1; not expected)
2020-06-21 15:12:09,159 INFO spawned: ‘nginx’ with pid 207
2020-06-21 15:12:10,643 INFO success: nginx entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
2020-06-21 15:12:19,179 INFO exited: nginx (exit status 1; not expected)
And so on. In the nginx log there’s the following:
2020/06/21 15:11:44 [emerg] 15#15: host not found in upstream “www.percona.com” in /etc/nginx/conf.d/pmm.conf:179
2020/06/21 15:11:49 [emerg] 154#154: host not found in upstream “www.percona.com” in /etc/nginx/conf.d/pmm.conf:179
2020/06/21 15:11:59 [emerg] 180#180: host not found in upstream “www.percona.com” in /etc/nginx/conf.d/pmm.conf:179
Anyone else having this problem?
Yep, firewalld again (see Cannot add remote MySQL instance) 
Forgot to disable it…