[Dovecot] auth failures

[Andreas Schulze]

Hello,

last week and today our dovecot pop3 server stopped responding.
Without any other logentries dovecot start to log only this:

Dec 12 09:14:12 mbox1 dovecot: auth: Error: ldap(testuser,192.0.2.110,<FBZH7lHtAQAK/FCj>): ldap_search(base=ou=accounts,dc=example,dc=de filter=(&(|(uid=testuser)(mail=testuser))(!(state=blocked)))) failed: Operations error

For every pop3 Session, ~2000 per Minute ..., over 10 Minutes
I send dovecot a SIGTERM. After dovecot was started again, all was fine again.

# doveconf -n
http://postmaster.datev.de/tmp/dovecot.conf

The LDAP-Server itself did resond to queries in the same timeframe. I know this because the MTA on the same host was able to deliver messages into mailboxes.

Any hints?

Thanks
Andreas

-- 
Andreas Schulze
Internetdienste | P252

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