Pierangelo Masarati wrote:

I have no possibility to setup a back-sql with mysql right now. Can you post your configuration? Can you post some (verbose) logs of operations affecting back-sql (e.g. with BACKSQL_TRACE manually #defined in back-sql/back-sql.h)? Can you step thru a search into backsql_search() and see if it gets called and why it doesn't get to contacting the rdbms?

I'm compiling with BACKSQL_TRACE defined right now.

After further prodding I have discovered...

ejabberd (a jabber daemon) makes connections to ldap, which it keeps open indefinitely. It appears mysql's odbc connector will time out an idle mysql connection after 8 hours. Since this is the slave system it's entirely possible for it not touch mysql connections for at least 8 hours.

If we restart mysql some ldap queries fail on back-sql portion until we kill ejabberd (to close it's ldap connections).

I'll give you logs with tracing enabled asap, but this looks like a big clue as to what is happening.