NDOUtils -> MySQL: queue recv error (recorded on video)

[PepeOnAchair]

Nice day...

I did make a video (link bellow) with the issue, but first:

Used versions:
Debian 9: Linux Nagios 4.9.0-11-amd64 #1 SMP Debian 4.9.189-3+deb9u2 (2019-11-11) x86_64 GNU/Linux
Nagios: 4.4.5 (cca 2700 hosts and cca 16000 services)
NDOUtils: 2.1.3, using "/usr/local/nagios/var/ndo.sock"
MySQL: mysql Ver 15.1 Distrib 10.1.45-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

I`d like to feed the Nagvis with data from Nagios through NDOUtils and MySQL. I followed this howto whn installing it: "https://support.nagios.com/kb/article/n ... tml#Debian".

Thinkgs looked fine, data were stored in MySQL databaze, I can read them... BUT after very short time, like in some tens seconds, data stops to be written into databaze.

When I run: watch systemctl status ndo2db.service
I can see what is on "ndo2db_status.JPG" in the attachment when writing data is stopped.
And every 30 seconds it prints new logs like: "... ndo2db[xyz]: Error: queue recv error."

In /etc/sysctl.conf I have:
kernel.msgmnb = 131072000
kernel.msgmax = 131072000
kernel.shmmax = 4294967295
kernel.shmall = 268435456

If I run:
systemctl restart ndo2db.service
or
service nagios restart
it fixes problem for another few tens of seconds...

Together with this new and not working NDO module:
broker_module=/usr/local/nagios/bin/ndomod.o config_file=/usr/local/nagios/etc/ndomod.cfg
I use:
broker_module=/usr/local/lib/mk-livestatus/livestatus.o /usr/local/nagios/var/rw/live
which works OK

You can see what it does on video here:
https://ulozto.net/file/xw6rLCIdYTYe/nd ... -video-mp4
password for downloading is: NDO

Does anyone know how to fix this "queue recv error" issue, please? I found some topics here about same problem, but there is no working solution.
Thank you a lot...
Pep.