[Xymon] IMAPS & POP3S tests

[Damien Martins]

Hi,

Since I upgraded a system to Debian 10 running Xymon client 4.3.28, my 
Xymon server (running version 4.3.28 on Debian 10) reports errors for 
IMAPS & POP3S tests.

This is weird, because I have another server, running Xymon 4.3.28 too, 
that is not reporting any issue.

My IMAPS & POPS3S daemon is dovecot 2.3.4.1-5+deb10u1

It is quiet complicated to find the logs for this test, so I don't know 
what is going wrong.

Sometimes, the test goes green for few minutes.

I tried configuring fail2ban to whitelist my Xymon server IP, and set 
dovecot to allow a large amount of connections, but this did not change 
anything.

Any help to investigate or locate IMAPS test logs would be appreciated.