After a device went down active ports are not getting pulled anymore

Hello together,

first of all: Thank you for creating and maintaining LibreNMS. Its a great piece of software which helps us a lot with our daily workloads.

I found something strange with our installation - if one of our routers (Mikrotik only) is not reachable (doesn’t matter how long it is not reachable) active ports are not getting pulled anymore. To give you a little bit more insight how we added our devices to LibreNMS:

-> Added Device manually with SNMP credentials
-> After the first discovery we normally disable all unneeded ports (some of our routers have > 1000 virtual ports which we do not want to pull everytime) and activate the “Enable selected port polling” via Misc-Options for that Host
-> We disabled some modules for these hosts as well which are not needed (for example: ARP-Table, IPMI, STP, Port-Stacking)

Now if we see any downtime on one of our routers everything works as expected when the device is reachable again except the port-pollling. The main view for that host shows an empty graph and we can see that there are “inactive” but no active ports [see picture 1]. If we switch to the Port subview we do not see any ports at all [see picture 2]. If we switch over to “Edit host” -> “Port Settings” all the ports are listed.
After i manually run the script collect-port-polling (./scripts/collect-port-polling.php -h 123) for that specific device the port-polling starts working again. The problem is not solved when runing the poller (./poller.php -h 123) or discovery via Web-UI manually.

I dont think this is intended behavior. Is there any chance to debug this further? If yes please be so kind and tell me which scripts / debug settings i should set and i will do so as soon as possible.

[email protected]:/opt/librenms# ./validate.php

Component Version
LibreNMS 1.53.1
DB Schema 2019_05_30_225937_device_groups_rewrite (135)
PHP 7.2.19-0ubuntu0.18.04.1
MySQL 10.1.40-MariaDB-0ubuntu0.18.04.1
RRDTool 1.7.0


[OK] Composer Version: 1.8.6
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct
[WARN] IPv6 is disabled on your server, you will not be able to add IPv6 devices.

Since im only able to post one image in my first post, i uploaded the three images to imgur: