Hello, I'm facing an issue where deleted emails keep re-appearing after my mailbox index gets recreated. I'm running version 2.2.36 of dovecot, but I tested the same scenario under 2.3.10. I'm also using mdbox, autoexpunge, and using dovecot replication.
I've had several instances now where some expunged emails show up again in a mailbox. I noticed this error:
doveadm: Error: Corrupted dbox file /var/mail/virtual/mailbox@domain.com/mdbox/storage/m.3228 (around offset=1988744): msg header has bad magic value
which caused the index to get rebuilt... however several times now, the indexes got rebuilt even though there doesnt seem like there was any error... so im not sure why that is.
lmtp(13910): Warning: fscking index file /var/mail/virtual/mailbox@domain/mdbox/storage/dovecot.map.index lmtp(13910): Warning: fscking index file /var/mail/virtual/mailbox@domain/mdbox/storage/dovecot.map.index lmtp(13910): Warning: mdbox /var/mail/virtual/mailbox@domain/mdbox/storage: rebuilding indexes
I'm not sure why these mails keep coming back though... or if there's anything that I can do to limit the number of emails that get restored.
I want to make sure expunged & purged emails stay expunged & purged. If I run a purge and then force index recreation... why would expunged emails come back? Shouldn't I expect them all to be deleted & purged? Does expunge not expunge all emails? (In production, I'm running autoexpunge but this test below shows what happens when I attempt to expunge everything)
doveadm search -u email@domain all | wc -l # output 22096
doveadm expunge -u email@domain mailbox '*' all doveadm search -u email@domain all | wc -l # output: 0
doveadm purge -u email@domain doveadm dump /var/mail/virtual/email@domain/mdbox/storage/ | grep -c 'ref.*\b0\b' # output: 0
doveadm force-resync -u email@domain Inbox # output: # doveadm(email@domain): Warning: fscking index file /var/mail/virtual/email@domain/mdbox/storage/dovecot.map.index # doveadm(email@domain): Warning: mdbox /var/mail/virtual/email@domain/mdbox/storage: rebuilding indexes # doveadm(email@domain): Warning: fscking index file /var/mail/virtual/email@domain/mdbox/storage/dovecot.map.index
doveadm search -u email@domain all | wc -l # output: 843
I would expect the output to be 0. Theoretically I deleted all emails and purged all emails. Nothing should be left on the disk? However... I can see there are still m.* files in mdbox/storage for the mailbox.
Overall, I'm not sure why the index got recreated... but I'm trying to limit the impact of mailbox corruption so that deleted emails do not come back if the index is somehow recreated again.
If I were to re-run expunge, purge, and force-resync a 2nd time... it does get emptied out, but I'm not looking to run force-resync intentially since it causes dataloss with mdbox, and re-running only expunge & purge doesn't seem to do anything.
Bojan Zelic Sr. IT Infrastructure Engineer