Dovecot 2.2.15 imap crash/panic (with core dumped)

[Timo Sirainen]

On 12 Nov 2014, at 05:32, Alessio Cecchi <alessio at skye.it> wrote:

> after upgrade to Dovecot >= 2.2.14rc1 sometimes I found this error/crash in the log (never happened with 2.2.13),
> 
> I'm the only one? Can be fix?
> 
> Nov 11 17:44:26 imap(info at myemail.com): Error: Corrupted transaction log file /home/domains/myemail.com/info/Maildir/dovecot.index.log seq 190: Invalid transaction log size (32756 vs 32772): /home/domains/myemail.com/info/Maildir/dovecot.index.log (sync_offset=32756)
> Nov 11 17:44:26 imap(info at myemail.com): Error: Log synchronization error at seq=0,offset=0 for /home/domains/myemail.com/info/Maildir/dovecot.index: Append with UID 10777, but next_uid = 10778
> Nov 11 17:44:26 imap(info at myemail.com): Error: /home/domains/myemail.com/info/Maildir/dovecot.index view syncing failed to apply changes
> Nov 11 17:44:26 imap(info at myemail.com): Panic: file index-sync.c: line 265 (index_mailbox_sync_next_expunge): assertion failed: (range->seq2 <= ctx->messages_count)

I can't really think of what would have started causing these. There aren't that big changes done to index handling code. I've also been running a ton of stress testing for Dovecot without these errors, so it's not a common problem at least. Although..:

> mail_nfs_index = yes
> mail_nfs_storage = yes

What kind of a setup is this? Are there multiple Dovecot backend servers and are you using director? These two settings never worked 100% and they're not supported anymore. In a single dovecot server / or multi-dovecot+director setup these can be "no".