Am 07.03.2018 um 19:51 schrieb Andrew Nichols via Info-cyrus:
Am 07.03.2018 um 17:00 schrieb Andrew Nichols via Info-cyrus:
Hello,

We run a cyrus-imap 2.5.11 server under FreeBSD and we are experiencing issues 
with TLS/STARTTLS negotiation failed entries in the log, which show as timeouts 
on the client side.   It?s all different email clients and even our monitoring 
experiencing these failures.  Other TLS services (https mostly) on the same 
server do not have these failures.  There are also times when these errors ramp 
up and happen to most TLS clients, which is only solved by restarting cyrus.    
Has anyone else experiences these issues or have any tips on where to look to 
figure out the root cause?
Has your server enough entropy?
Specially cloud servers with no physical ports can run low on entropy
and the random number generator used for SSL/TLS stuff needs to way
until it is filled up again.

To check the amount of bytes of entropy currently available, use

|cat /proc/sys/kernel/random/entropy_avail From
https://serverfault.com/questions/214605/gpg-does-not-have-enough-entropy|


That’s what I had though at the start, but this is a physical server and 
/dev/random in FreeBSD is the same as /dev/urandom so it doesn’t block once 
seeded.  Also, when this starts happening the other services on the machine 
that need entropy aren’t affected.

Do you monitor the number of cyrus processes (pop/imap/sieve/... )
Perhaps you reach the configured limit?

André
----
Cyrus Home Page: http://www.cyrusimap.org/
List Archives/Info: http://lists.andrew.cmu.edu/pipermail/info-cyrus/
To Unsubscribe:
https://lists.andrew.cmu.edu/mailman/listinfo/info-cyrus

Reply via email to