Cyrus terminated abnormally

Hi amd64 friends!

I have recently had some woes with my Cyrus daemon, and I have not been
successful at troubleshooting it myself. I did a system update over the
weekend, and ever since then Cyrus works for a bit and then dies with
this in the logs:

Aug  6 20:19:43 skull imaps[16458]: IOERROR: opening
/var/imap/user_deny.db: No such file or directory
Aug  6 20:19:43 skull imaps[16458]: accepted connection
Aug  6 20:19:43 skull master[17776]: about to exec /usr/lib64/cyrus/imapd
Aug  6 20:19:43 skull imaps[17776]: executed
Aug  6 20:19:43 skull imaps[16458]: imapd:Loading hard-coded DH parameters
Aug  6 20:19:43 skull imaps[16458]: EOF in SSL_accept() -> fail
Aug  6 20:19:43 skull imaps[16458]: imaps TLS negotiation failed:
[2001:470:8:97a:9829:b3a:e34c:1b2]
Aug  6 20:19:43 skull imaps[16458]: Fatal error: tls_start_servertls()
failed
Aug  6 20:19:43 skull master[16810]: process 16458 exited, status 75
Aug  6 20:19:43 skull master[16810]: service imaps pid 16458 in BUSY
state: terminated abnormally

When this happens, none of my clients can connect to the server until I
restart the service. Sometimes when I restart it, it will run for hours,
sometimes only for minutes. I haven't been able to identify a specific
activity that causes it to have this issue.

The update did involve a rebuild of cyrus-imap-admin, I think due to a
Perl update (or maybe it was an auto rebuild? I can't remember.) I can't
think of why that would cause this, but it was the only obviously
related package update.

I can't think of what steps I can take to look into this in a more
informative way. Searching for these error messages reveals many people
with many different kinds of problems (and posts dating back for a
decade!) so it is difficult to narrow down what my problem is. I have
tried to raise maxchild to large values (100) and to unlimited (-1) and
that does not resolve the issue.

Any ideas? Do any of you use Cyrus? Is your server still working?

I've considered migrating to Dovecot if I can't figure this out, so I'd
recommend opinions on Cyrus vs. Dovecot as a side thread.

-- 
R

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