Comment 4 for bug 2015103

Keystone retries the identity-service-relation-changed hook several times, also after the MySQL cluster has clustered, but it keeps failing with this message in the keystone log:

===================
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/sqlalchemy/engine/base.py", line 1802, in _execute_context
    self.dialect.do_execute(
  File "/usr/lib/python3/dist-packages/sqlalchemy/engine/default.py", line 732, in do_execute
    cursor.execute(statement, parameters)
  File "/usr/lib/python3/dist-packages/pymysql/cursors.py", line 148, in execute
    result = self._query(query)
  File "/usr/lib/python3/dist-packages/pymysql/cursors.py", line 310, in _query
    conn.query(q)
  File "/usr/lib/python3/dist-packages/pymysql/connections.py", line 548, in query
    self._affected_rows = self._read_query_result(unbuffered=unbuffered)
  File "/usr/lib/python3/dist-packages/pymysql/connections.py", line 775, in _read_query_result
    result.read()
  File "/usr/lib/python3/dist-packages/pymysql/connections.py", line 1156, in read
    first_packet = self.connection._read_packet()
  File "/usr/lib/python3/dist-packages/pymysql/connections.py", line 692, in _read_packet
    packet_header = self._read_bytes(4)
  File "/usr/lib/python3/dist-packages/pymysql/connections.py", line 748, in _read_bytes
    raise err.OperationalError(
pymysql.err.OperationalError: (2013, 'Lost connection to MySQL server during query')
===================

From comment #1 I understand that retrying the hook should solve the problem, but that does not seem to be the case.

If I switch the leader of Keystone it does pass this hook and starts updating the endpoints like normal. It is possible that the certificates can not be updated for the leader units and that that causes the connection issue?