Cur folder grows exponentially overnight

I have a user with 500MB worth of email whose folder just grew from 500MB to 4.7GB, with a “cur” folder suddenly taking up 4.2GB of space literally out of nowhere.

The server had exactly 4.2GB more of free space yesterday, and the user has done nothing on his end other than reading his 10 emails a day just like every other day.

What in the world has happened?

root@mb:~# du -sh /home/user-data/mail/mailboxes/domain/user/*
4.2G    /home/user-data/mail/mailboxes/domain/user/cur
44K     /home/user-data/mail/mailboxes/domain/user/dovecot.index
2.6M    /home/user-data/mail/mailboxes/domain/user/dovecot.index.cache
12K     /home/user-data/mail/mailboxes/domain/user/dovecot.index.log
40K     /home/user-data/mail/mailboxes/domain/user/dovecot.index.log.2
4.0K    /home/user-data/mail/mailboxes/domain/user/dovecot.mailbox.log
144K    /home/user-data/mail/mailboxes/domain/user/dovecot-uidlist
4.0K    /home/user-data/mail/mailboxes/domain/user/dovecot-uidvalidity
0       /home/user-data/mail/mailboxes/domain/user/dovecot-uidvalidity.58a8ad85
1.2M    /home/user-data/mail/mailboxes/domain/user/lucene-indexes
0       /home/user-data/mail/mailboxes/domain/user/maildirfolder
725M    /home/user-data/mail/mailboxes/domain/user/new
4.0K    /home/user-data/mail/mailboxes/domain/user/subscriptions
4.0K    /home/user-data/mail/mailboxes/domain/user/tmp


somehow a colleague of my user had a stuck geary program sending him extremely large emails and don’t ask me how, but I logged into my user’s account, deleted 61 emails, and the size went from a total of 4.7GB to 250MB. How could this happen?

Not clear what you mean by “how could this happen”…well, your user was being sent email and the Mail-in-a-Box server was accepting them…as it’s designed to do. By default miab does not implement any quotas, so your user will be able to accept email until you run out of disk space :wink:

Were you expecting something else to happen when email is sent to your user?

Ok good to know that there are no receiving quotas, as someone who is always increasing file size limits everywhere, I do still think it’s probably a stability issue if I can simply send someone a 500MB or greater email repeatedly and instantly fill up their MIAB server disk, but I know the solution would be hard to fine-tune and implement.