==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): current
- Deployed with iRedMail Easy or the downloadable installer? Your support
- Linux/BSD distribution name and version: Debian
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? Yes
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
Got this twice last night and it was the first time:

Traceback (most recent call last):
  File "/opt/iredapd/tools/cleanup_db.py", line 34, in <module>
    total_before = sql_count_id(conn_iredapd, 'throttle_tracking')
  File "/opt/iredapd/tools/../tools/__init__.py", line 81, in sql_count_id
    what='count(%s) as total' % column)
  File "/usr/lib/python2.7/dist-packages/web/db.py", line 699, in select
    return self.query(qout, processed=True)
  File "/usr/lib/python2.7/dist-packages/web/db.py", line 658, in query
    db_cursor = self._db_cursor()
  File "/usr/lib/python2.7/dist-packages/web/db.py", line 570, in _db_cursor
    return self.ctx.db.cursor()
  File "/usr/lib/python2.7/dist-packages/web/db.py", line 511, in _getctx
    self._load_context(self._ctx)
  File "/usr/lib/python2.7/dist-packages/web/db.py", line 522, in _load_context
    ctx.db = self._connect(self.keywords)
  File "/usr/lib/python2.7/dist-packages/web/db.py", line 550, in _connect
    return self.db_module.connect(**keywords)
  File "/usr/lib/python2.7/dist-packages/MySQLdb/__init__.py", line 81, in Connect
    return Connection(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/MySQLdb/connections.py", line 204, in __init__
    super(Connection, self).__init__(*args, **kwargs2)
_mysql_exceptions.OperationalError: (2003, 'Can\'t connect to MySQL server on \'127.0.0.1\' (111 "Connection refused")')