Thanks for the quick answer. I realised, that the error didn't occur since quite a while, opposed to what our client suggested. Back then I activated the two workarounds (imap_client_workarounds = outlook-idle delay-newmail) and increased mail_max_userip_connections for IMAP.
Is it possible that those could have improved the situation? For now I don't have a way of reproducing the problem, so I will have to wait for an error to happen. Until then I will consider the problem as "Solved until happens again ;-) ", since the last error occured a while back (as mentioned above). >> Mar 6 08:26:31 mail02 dovecot: IMAP(u...@example.com): >> fdatasync(/data/vmail/example.com/user/dovecot-uidlist) failed: Input/output >> error >> Mar 6 08:42:29 mail02 dovecot: IMAP(u...@example.com): Maildir >> /data/vmail/example.com/user: Expunged message reappeared, giving a new UID >> (old uid=1522, file=1326961561.V15I4d8562M567017.mail02:2,Sad) >> Mar 6 08:42:29 mail02 dovecot: IMAP(u...@example.com): Maildir >> /data/vmail/example.com/user: Expunged message reappeared, giving a new UID >> (old uid=1523, file=1326705103.V15I90105M613353.mail01:2,Sad) >> Mar 6 08:42:29 mail02 dovecot: IMAP(u...@example.com): >> /data/vmail/example.com/user/dovecot-uidlist: Duplicate file entry at line >> 4: 1326961561.V15I4d8562M567017.mail02:2,Sad (uid 1522 -> 1598) .. >> My suspicion/speculation what happens is the following: >> Multiple users are accessing the Mailbox from their offices (all on the same >> server), one (or more) uses the Webmail or accesses the Mailbox from a >> different IP. >> Somehow this leads to problems with Locks on NFS, which leads to the crash. >Yes, most likely this is what's happening. Although your errors are more >severe than what normally happens. I guess your NFS server is also partially >to blame (microsecond resolution timestamps are at least helpful). I had a quick look a tour NFS (NetApp), but didn't find anything useful. In case the problem persists, I will check with the coworker responsible for NetApp. I will check what sort of locking is used by postfix, since I'm not sure if postfix and dovecot are configured to use the same mechanisms. If not, I think it could be part of the Problem. >> I have no idea how to solve this problem and any help is greatly appreciated. >The only way to fully fix this is: http://wiki2.dovecot.org/Director Unfortunately that is not an option right now, but I will keep it in mind. Thanks again.
