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Matt Simerson wrote:
| Problem:  vpopmail authentications failing randomly

| delivery 14578: failure: vmysql:_sql_error
| [1]:_Can't_create_database_'vpopmail'._Database_exists/
| vmysql:_sql_error[3]:_No_Database_Selected/
| Sorry,_no_mailbox_here_by_that_name._vpopmail_(#5.1.1)/
| delivery 14641: failure: vmysql:_sql_error
| [1]:_Can't_create_database_'vpopmail'._Database_exists/
| vmysql:_sql_error[3]:_No_Database_Selected/
| Sorry,_no_mailbox_here_by_that_name._vpopmail_(#5.1.1)/
| There are no errors reported in MySQL's .err log. There are no other
| related errors reported in the system logs. The MySQL load is quite
| light, with less than one query executed every few seconds.  The
| system load is also fairly light, mostly hovering between 0.4 and 0.5.
| All the symptoms are indicative of vpopmail having an issue with
| MySQL, so I set up a little perl script to test for me while I tried
| to replicate the problem.

| So, anyone got ideas on how to debug this issue further?

Hi, Matt.  I have previously had this problem.  You are indeed
correct.  It is a problem with vpopmail talking with MySQL.
Unfortunately, MySQL, as you said, reports nothing, regardless
of the fact that vpopmail is returning an error.  The series
of events you're seeing in the vpopmail logs, is vpopmail
receiving a 'Read error, MySQL server has gone away' during
a database read.  vpopmail then thinks the database may not
exist, and it tries to create the database as if it was
starting from scratch.  I spent *hours* looking into *WHY*
this occurs with no result other than the fact that it is
indeed on MySQL's end.   This is what I have yet so far
figured out:

1) vpopmail connects and succesfully authenticates,
~   and switches to the database.

2) vpopmail tries to read and receives the 'Server gone
~   away' message.

3) The MySQL server does not document via error or debugging
~   messages the actual cause of the error, but if it did,
~   we might be able to determine the root cause.

In my trials, I tried adjusting packet sizes, timeouts on both
vpopmail, and MySQL, turning on debugging, recompiling with
various settings, etc.  The interesting thing about the problem
is that it just simply crops out of out no where, and simply
will not go away.  I would love to get this documented on
qmailwiki.org, but as of yet, I've had no luck determining
the cause, or finding a solution.  You may wish to try upgrading
or downgrading MySQL.

If you find anything else, please let me know.


- --
~    Matt Brookings <[EMAIL PROTECTED]>       GnuPG Key 7D7E5F37
~    Software developer                     Systems technician
~    Inter7 Internet Technologies, Inc.     (815)776-9465
Version: GnuPG v1.2.6 (GNU/Linux)


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