[Serusers] Re: Strange error on registration - Still a Problem in a Certain Scenario

[reticent]

I was looking back through the mailing list archives and i found this
email regarding failed inserts into the location table of a database due
to duplicate entries and there is still a situation where this problem
will occur.

For the full original Thread, this is where is starts
http://lists.iptel.org/pipermail/serusers/2004-April/007151.html
http://lists.iptel.org/pipermail/serusers/2004-April/thread.html#7173

Basically the issue is that the database has an entry for a user that
SER does not have in memory so when a registration comes in SER uses an
INSERT statement instead of an UPDATE which fails because a key 
(username, contact, domain) already exists for the user in the database.

The situation where it still occurs is when the database goes away and
during the hiatus a registration expires, SER wipes the registration
from memory and fails on the database delete.

SER will recover from this situation only when it is stopped and
started, this complicates load balanced situations where it is expected
that SER can recover from certain failures (database failures in this
case) without any administrive intervention