On 26.3.2012, at 18.25, Müller Lukas wrote: > 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?
Unlikely. >>> 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 guess you just had very bad luck. NetApp has a good NFS implementation and normally works fine with Dovecot.