lmtpd: failed to mmap file /var/lib/imap/deliver.db.NEW (in reply to end of DATA command) - email

Question

Good day!
After installing and running kolab letters delivered instantly. But after a few days letters to local destinations have become delivered with a delay. Over time, they are delivered, but the delay may be several hours. An example of the path of the letter:
root#myhost:~# cat /var/log/mail.log | grep 7AA7935B1FC
Jan 12 11:31:03 myhost postfix/smtpd[19494]: 7AA7935B1FC:
client=localhost[127.0.0.1]
Jan 12 11:31:05 myhost postfix/cleanup[19492]: 7AA7935B1FC:
message-id=<20160112093103.7AA7935B1FC#mail.myhost.com>
Jan 12 11:31:05 myhost postfix/qmgr[7021]: 7AA7935B1FC:
from=<noreply#myhost.com>, size=1279, nrcpt=3 (queue active)
Jan 12 11:31:05 myhost lmtpunix[19631]: Delivered:
<20160112093103.7AA7935B1FC#mail.myhost.com> to mailbox:
myhost.com!user.user1
Jan 12 11:31:06 myhost postfix/lmtp[19617]: 7AA7935B1FC: to=<user1#myhost.com>, relay=mail.myhost.com[/var/lib/imap/socket/lmtp], delay=2.6, delays=2/0.01/0/0.59, dsn=4.3.0, status=deferred (host
mail.myhost.com[/var/lib/imap/socket/lmtp] said: 421 4.3.0 lmtpd:
failed to mmap /var/lib/imap/deliver.db.NEW file (in reply to end of
DATA command))
Jan 12 11:31:06 myhost postfix/lmtp[19617]: 7AA7935B1FC: to=<user2#myhost.com>, relay=mail.myhost.com[/var/lib/imap/socket/lmtp], delay=2.7, delays=2/0.01/0/0.68, dsn=4.4.2, status=deferred (lost connection with mail.myhost.com[/var/lib/imap/socket/lmtp] while sending end of data
-- message may be sent more than once
Jan 12 11:31:07 myhost postfix/lmtp[19617]: 7AA7935B1FC: to=<user3#myhost.com>, relay=mail.myhost.com[/var/lib/imap/socket/lmtp], delay=2.7, delays=2/0.01/0/0.68, dsn=4.4.2, status=deferred (lost connection with mail.myhost.com[/var/lib/imap/socket/lmtp] while sending end of data
-- message may be sent more than once)
Currently mailq features a variety of messages in queue. An example of one of these:
7BBDF35B123 6162 Tue Jan 12 13:19:24 user#rambler.ru (delivery temporarily suspended: lost connection with mail.myhost.com[/var/lib/imap/socket/lmtp] while sending end of data -- message may be sent more than once) user4#myhost.com
-- 11667 Kbytes in 327 Requests.
I think that the main reason is described here:
lmtp: failed to mmap /var/lib/imap/deliver.db.NEW file
But, unfortunately, not been able to find a solution.

Answer 1

The problem was solved according to this recommendation: http://lists.kolab.org/pipermail/users-de/2015-May/001998.html
Stop Services cyrus-imap and postfix
Delete files deliver.db.NEW and deliver.db in the directory /var/lib/imap/
Start the services and the file deliver.db is automatically created
Restart the queue: postsuper -r ALL
Some of the letters delivered from the queue again.
Proposed cause: after installing and start services on the new server users download messages en masse in the format *.eml, downloaded from the last post. Perhaps these actions somehow overflowed index files.
P.S.: Unfortunately, the solution was temporary: the situation described above is repeated periodically :(