Comment 14 for bug 1915842

I feel like ive bumped into this issue again on a heat unit when using the charmers-next mysql-router

heat unit 1 went into error while trying to migrate the database:

2021-03-28 06:21:23 INFO juju-log shared-db:146: Migrating the heat database.
2021-03-28 06:21:26 DEBUG shared-db-relation-changed 2021-03-28 06:21:26.752 87238 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 10 attempts left.: oslo_db.exception.DBConnectionError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on '127.0.0.1' ([SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1123))")^[[00m
2021-03-28 06:21:36 DEBUG shared-db-relation-changed 2021-03-28 06:21:36.770 87238 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 9 attempts left.: oslo_db.exception.DBConnectionError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on '127.0.0.1' ([SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1123))")^[[00m

2021-03-28 06:23:09 WARNING shared-db-relation-changed ERROR: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on '127.0.0.1' ([SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1123))")
2021-03-28 06:23:09 WARNING shared-db-relation-changed (Background on this error at: http://sqlalche.me/e/e3q8)
2021-03-28 06:23:09 DEBUG shared-db-relation-changed OpenStack Release: {}
2021-03-28 06:23:09 WARNING shared-db-relation-changed Traceback (most recent call last):
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/shared-db-relation-changed", line 470, in <module>
2021-03-28 06:23:09 WARNING shared-db-relation-changed main()
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/shared-db-relation-changed", line 463, in main
2021-03-28 06:23:09 WARNING shared-db-relation-changed hooks.execute(sys.argv)
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/charmhelpers/core/hookenv.py", line 945, in execute
2021-03-28 06:23:09 WARNING shared-db-relation-changed self._hooks[hook_name]()
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/charmhelpers/core/host.py", line 725, in wrapped_f
2021-03-28 06:23:09 WARNING shared-db-relation-changed return restart_on_change_helper(
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/charmhelpers/core/host.py", line 749, in restart_on_change_helper
2021-03-28 06:23:09 WARNING shared-db-relation-changed r = lambda_f()
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/charmhelpers/core/host.py", line 726, in <lambda>
2021-03-28 06:23:09 WARNING shared-db-relation-changed (lambda: f(*args, **kwargs)), restart_map, stopstart,
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/shared-db-relation-changed", line 272, in db_changed
2021-03-28 06:23:09 WARNING shared-db-relation-changed migrate_database()
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/var/lib/juju/agents/unit-heat-1/charm/hooks/heat_utils.py", line 319, in migrate_database
2021-03-28 06:23:09 WARNING shared-db-relation-changed check_call(['heat-manage', 'db_sync'])
2021-03-28 06:23:09 WARNING shared-db-relation-changed File "/usr/lib/python3.8/subprocess.py", line 364, in check_call
2021-03-28 06:23:09 WARNING shared-db-relation-changed raise CalledProcessError(retcode, cmd)
2021-03-28 06:23:09 WARNING shared-db-relation-changed subprocess.CalledProcessError: Command '['heat-manage', 'db_sync']' returned non-zero exit status 1.

testrun found at: https://solutions.qa.canonical.com/testruns/testRun/7a67372e-7c99-4213-9a26-d68f2e71399e