Device Dependency Not Honured

Hi All,

We have an ongoing issue with device dependencies in LibreNMS;

root@gwsmhcti02:/opt/librenms# ./validate.php

Component Version
LibreNMS 1.54
DB Schema 2019_07_03_132417_create_mpls_saps_table (139)
PHP 7.2.19-0ubuntu0.18.04.1
MySQL 10.1.40-MariaDB-0ubuntu0.18.04.1
RRDTool 1.7.0
SNMP NET-SNMP 5.7.3
====================================

[OK] Composer Version: 1.8.6
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct
[WARN] Some devices have not been polled in the last 5 minutes. You may have performance issues.
[FIX]:
Check your poll log and see: Performance - LibreNMS Docs
Devices:
nta-sw04

We have a large number of sites where we monitor the site router and the switches behind it. We have setup Device Dependencies for all devices. Here is an example.

nls-sw01

nls-r1-gm15957

Both devices are currently down;

However, alerts have been transported for both devices?

nls-sw01

nls-r1-gm15957

Why would this be? We have issues with not all devices being polled in a single cycle, would this have a bearing? However, these devices have been down for over an hour and we still get alerts transported for both devices?

Regards,

Duncan

Device dependencies are not guaranteed to work, unless you are using the fast ping check.

The default of alerts is to repeat on an interval. Change that setting if you don’t want repeat. Once an alert is triggered it will keep triggered until it is resolved.

Hi Murrant,

Thanks for the quick response. I will turn this on;

https://docs.librenms.org/Extensions/Fast-Ping-Check/

However, it does state on the page that this might not fix the problem;

Device dependencies

The ping.php script respects device dependencies, but the main poller does not (for technical reasons). However, using this script does not disable the icmp check in the poller and a child may be reported as down before the parent.

Duncan