micah <micah@riseup.net> wrote:

Now, about 50 users have a problem where their indexes are corrupted. Dovecot tries to fix them, but for some reason it is failing. The users are seeing their mails duplicated and they cannot delete mails. I can see in the logs dovecot detecting this and trying to rebuild operations during delivery and imap login, but its repeating over and over and over. For one user, I've seen more than 4k lines in the logs about this.

If i try to do doveadm force-resync -u username INBOX

I get this:

doveadm(nuffsaid): Warning: mdbox /n/nuffsaid/mdbox/storage: Inconsistency in map index (3494,32332 != 3494,383536)

I think mdbox is sensitive to index corruption. mbox/maildir indices can be rebuilt, but data loss can result if mdbox indices are corrupted:

https://wiki2.dovecot.org/MailboxFormat/dbox

"Grubert, Gordon" <gordon.grubert+lists@uni-greifswald.de> then writes:

we had the same problem after a system failure. Our problem could be solved by

rm /PATH/USER/mdbox/storage/dovecot.map.index* doveadm -D -v force-resync -u USER INBOX

Not sure given the above URL whether this will solve your problem of make it far worse. Better back up what you have before trying anything.

Joseph Tam <jtam.home@gmail.com>