hammer.py sometimes cannot start mariadb service on alpine
This is really a copy of #3547 (closed) which did not fix the issue entirely, although it may have made it occur less frequently.
After running rc-service mariadb restart, this error is displayed: start-stop-daemon: /usr/bin/mysqld_safe is already running.
There were previous tested attempts to fix it:
Although the issue is intermittent and not easily replicable locally, hence this issue. You can see it happen again here: https://jenkins.aws.isc.org/job/kea-dev/job/pkg/1641/execution/node/256/log/.