Mosquitto ABRT when started

[SergeyVAppricot]

Mosquitto version 1.6.9.1. Platform Ubuntu 20.04. Use in bridge mode.

mosquitto.conf

pid_file /var/run/mosquitto.pid
persistence false
persistence_location /var/lib/mosquitto/
log_dest file /var/log/mosquitto/mosquitto.log
include_dir /etc/mosquitto/conf.d

mosquito.service

[Unit]
Description=Mosquitto MQTT v3.1/v3.1.1 Broker
Documentation=man:mosquitto.conf(5) man:mosquitto(8)
After=network-online.target
Wants=network-online.target

[Service]
Type=notify
NotifyAccess=main
ExecStart=/usr/sbin/mosquitto -c /etc/mosquitto/mosquitto.conf
ExecReload=/bin/kill -HUP $MAINPID
Restart=on-failure

[Install]
WantedBy=multi-user.target

When mosquitto.service started, get this error log:

мар 24 21:16:28 fando-1147 systemd[1]: mosquitto.service: Main process exited, code=dumped, status=6/ABRT
мар 24 21:16:28 fando-1147 systemd[1]: mosquitto.service: Failed with result 'core-dump'.
мар 24 21:16:28 fando-1147 systemd[1]: mosquitto.service: Scheduled restart job, restart counter is at 8.
мар 24 21:16:28 fando-1147 systemd[1]: Stopped Mosquitto MQTT v3.1/v3.1.1 Broker.
мар 24 21:16:28 fando-1147 systemd[1]: Starting Mosquitto MQTT v3.1/v3.1.1 Broker...
мар 24 21:16:28 fando-1147 mosquitto[16662]: 1648145788: Loading config file /etc/mosquitto/conf.d/vernemq.conf
мар 24 21:16:28 fando-1147 mosquitto[16662]: [20558.243183]~DLT~16662~INFO     ~FIFO /tmp/dlt cannot be opened. Retrying later...
мар 24 21:16:28 fando-1147 systemd[1]: Started Mosquitto MQTT v3.1/v3.1.1 Broker.
мар 24 21:16:35 fando-1147 mosquitto[16662]: mosquitto: /build/mosquitto-kshoW_/mosquitto-1.6.9/src/loop.c:730: loop_handle_reads_writes: Assertion `pollfds[context->pollfd_index].fd == context->sock' failed.

What to look out for?

[ralight]

If this is still a problem for you, I'm afraid I can't do much about the version on ubuntu 20.04 directly. I would suggest looking at the mosquitto project ppa: https://launchpad.net/%7Emosquitto-dev/+archive/mosquitto-ppa/ or using the snap package: https://snapcraft.io/mosquitto