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We have a problem with qpopper on our system. Once every 2 to 3 days we have a situation where qpopper can no-longer authenticate any users. It responds to requests on port 110 but authentication just hangs. It is
using pamdb for authentication.
When this problem happens, no-one but root can login via any of the other services. I downloaded a pam test script that uses perl to check a password using pam and that fails also.
If we leave this problem too long we end up with too many pop sessions,
and the number of open files on the system being exhausted, but that seems to be a symptom of the problem since when the problem starts we
are well below the maximum number of allowed open files.
I have turned on debugging for the pwdb module in the /etc/pam.d/qpop
but all that seems to show is successful and failed authentication
attempts and while we are having the problem it appears to continue as
Does anyone have any ideas on how I might work out what is going on or
at the least be able to recover from this situation without having to
reboot the entire box. I have tried shutting down the inet service but
the qpopper processes remain open so after doing a killall on
in.qpopper, they disappear but the pam authentication still fails.