For the sake of good order I will post a bit more information on this.
The topic is still closed for me though as it seems to have solved itself over time.
The issue seems to have been caused by a System Reboot that I did yesterday.
These emails were sent to postmaster@mydomain.com 1 minute after the reboot (or possibly during the reboot(?)).
Hope that will be helpful for someone at some stage.
# EMAIL 1:
Cron <sogo@server> /usr/sbin/sogo-tool expire-sessions 30; /usr/sbin/sogo-ealarms-notify
2017-01-08 08:00:36.184 sogo-tool[669:669] ERROR: could not open MySQL4 connection to database 'sogo': Can't connect to MySQL server on '127.0.0.1' (111)
<0x0xe22890[GCSChannelManager]> could not open channel <MySQL4Channel[0x0xf2f400] connection=0x(null)> for mysql://127.0.0.1/sogo/sogo_sessions_folder
<0x0xe22890[GCSChannelManager]> will prevent opening of this channel 5 seconds after 2017-01-08 08:00:36 -0500
2017-01-08 08:00:36.216 sogo-tool[669:669] Can't aquire channel
2017-01-08 08:00:36.790 sogo-ealarms-notify[791:791] ERROR: could not open MySQL4 connection to database 'sogo': Can't connect to MySQL server on '127.0.0.1' (111)
<0x0xc6f6c0[GCSChannelManager]> could not open channel <MySQL4Channel[0x0xaed890] connection=0x(null)> for mysql://127.0.0.1/sogo/sogo_alarms_folder
<0x0xc6f6c0[GCSChannelManager]> will prevent opening of this channel 5 seconds after 2017-01-08 08:00:36 -0500
# EMAIL 2:
Cron <root@server> python /opt/iredapd/tools/spf_to_greylist_whitelists.py >/dev/null
Traceback (most recent call last):
File "/opt/iredapd/tools/spf_to_greylist_whitelists.py", line 320, in <module>
qr = conn.select('greylisting_whitelist_domains', what='domain')
File "/usr/lib/python2.7/site-packages/web/db.py", line 682, in select
return self.query(qout, processed=True)
File "/usr/lib/python2.7/site-packages/web/db.py", line 643, in query
db_cursor = self._db_cursor()
File "/usr/lib/python2.7/site-packages/web/db.py", line 566, in _db_cursor
return self.ctx.db.cursor()
File "/usr/lib/python2.7/site-packages/web/db.py", line 507, in _getctx
self._load_context(self._ctx)
File "/usr/lib/python2.7/site-packages/web/db.py", line 518, in _load_context
ctx.db = self._connect(self.keywords)
File "/usr/lib/python2.7/site-packages/web/db.py", line 546, in _connect
return self.db_module.connect(**keywords)
File "/usr/lib64/python2.7/site-packages/MySQLdb/__init__.py", line 81, in Connect
return Connection(*args, **kwargs)
File "/usr/lib64/python2.7/site-packages/MySQLdb/connections.py", line 193, in __init__
super(Connection, self).__init__(*args, **kwargs2)
_mysql_exceptions.OperationalError: (2003, "Can't connect to MySQL server on '127.0.0.1' (111)")
# EMAIL 3:
Cron <root@server> python /opt/iredapd/tools/cleanup_db.py >/dev/null
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/site-packages/web/db.py", line 682, in select
return self.query(qout, processed=True)
File "/usr/lib/python2.7/site-packages/web/db.py", line 643, in query
db_cursor = self._db_cursor()
File "/usr/lib/python2.7/site-packages/web/db.py", line 566, in _db_cursor
return self.ctx.db.cursor()
File "/usr/lib/python2.7/site-packages/web/db.py", line 507, in _getctx
self._load_context(self._ctx)
File "/usr/lib/python2.7/site-packages/web/db.py", line 518, in _load_context
ctx.db = self._connect(self.keywords)
File "/usr/lib/python2.7/site-packages/web/db.py", line 546, in _connect
return self.db_module.connect(**keywords)
File "/usr/lib64/python2.7/site-packages/MySQLdb/__init__.py", line 81, in Connect
return Connection(*args, **kwargs)
File "/usr/lib64/python2.7/site-packages/MySQLdb/connections.py", line 193, in __init__
super(Connection, self).__init__(*args, **kwargs2)
_mysql_exceptions.OperationalError: (2003, "Can't connect to MySQL server on '127.0.0.1' (111)")