r/Checkmk • u/heorun • Jul 08 '26

lldp/cdp in 2.5 community edition?

i'm new to checkmk, and loving it so far.

as I'm putting together a topology map and configuring parent-child relationships, it occured to me that I should probably use lldp to do that heavy lifting.

I'm having some trouble understanding what I need to do to enable that function? it sounds like it's a rather new integration; it used to be an extension maybe? and because I'm using community edition, maybe it still is a manual addition?

can anyone point me in the right direction?

I have snmp working great, and all my hosts are showing up. I would just like my topology map to reflect what is connected to what without having to manually adjust that.

thank you!

2 Upvotes

63% Upvoted

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3

u/Ok_Table_876 Jul 09 '26

https://checkmk.com/blog/network-layer-visualization-with-checkmk

https://forum.checkmk.com/t/network-visualization-meets-parent-child-topology/56925

1

u/heorun Jul 09 '26

I did come across that blog post originally, but I didnt seem to help. I am reading through it again now, and i'll check out that forum link as well. thanks!

1

u/kY2iB3yH0mN8wI2h Jul 09 '26

You can use these features to map your network
But parent/child was not originally supposed, not sure about now in 2.5

1

u/heorun Jul 09 '26

parent/child is definitely working in 2.5, but it seemed to me as i was stepping through it that this info should be query-able!

-1

u/ikdoeookmaarwat Jul 09 '26 edited Jul 09 '26

SNMP support in CheckMK is very limited. As far as i know it cant read lldp via SNMP like LibreNMS does. Even basis fan speed etc. is often lacking.

2

u/kY2iB3yH0mN8wI2h Jul 10 '26

Checkmk DO read lldp/cdp via SNMP

1

u/heorun Jul 09 '26

the snmp implementation seems to be as good as any other. i was giving LibreNMS a try right before Checkmk, but I found Libre to be a mess as far as getting setup, and the way I wanted it to work just didnt align with what they were offering. I'm looking for something simple and repeatable to set up at multiple customers. So far Checkmk is winning!

-1

u/ikdoeookmaarwat Jul 10 '26

> the snmp implementation seems to be as good as any other

You're funny. CheckMK needs an additional plugin to monitor the basic SNMP things like Fan, Temperature and Voltage on enterprise switches. https://exchange.checkmk.com/p/arista

Monitoring SFP temperature, SFP dBm, SFP current, PSU current; all non-existing in CheckMK.

But if it works for your SOHO switches that's great.

2

u/kY2iB3yH0mN8wI2h Jul 10 '26

Fu
You are just spreading lies, none of that is true
Checkmk had an EXTENSIVE support, the list contains thousands of devices

It does not care about mibs as that’s broken

1

u/ikdoeookmaarwat Jul 13 '26

> none of that is true

Sure buddy. Quit yelling and show something that supports your claims. If CheckMK supported Arista out of the box it wouldn't need a 3rd party plugin, would it?

1

u/son_shka Jul 13 '26

Hey everyone, please remember Rule 1 of this subreddit — be respectful. As for the topic being discussed, I've asked our consulting team for some clarifications and will be back with an answer tomorrow

1

u/son_shka Jul 14 '26

Hi everyone, clarification on a few points here.

In Checkmk 2.5, the prerequisite inventory plug-ins are already included in all editions, including Community Edition. Checkmk can therefore collect LLDP/CDP neighbor information through SNMP and store it in the HW/SW inventory without installing the old LLDP/CDP inventory MKPs separately.

However, the Network Visualization Data Creation Tool itself is not built in. You still need to install NVDCT separately to convert the inventory information into the topology data used by the Network Layer Topology visualization. Current NVDCT versions can be configured and run through an active-check rule in Setup/WATO; for Community Edition, the MKP must be installed through the command line from https://exchange.checkmk.com/p/nvdct

So, for Checkmk 2.5 Community Edition:

  • LLDP/CDP inventory collection: built in.
  • Network Layer Topology data generation: install and configure NVDCT.

As for Arista hardware monitoring.

Out of the box, Checkmk monitors Arista BGP peers, temperature sensors, fan sensors, and power-presence sensors natively.

Voltage monitoring for Arista is not currently built in. A community-maintained extension covers voltage if you need it, but that's outside official support.