Absolute Beginner Here and Just Confusing Myself.

[StuartD]

This is all on Zabbix 7.

I am trying to wrap my head around discovery (if that's the right word) of aspects of a router via SNMP. We have installed the latest 'Cisco IOS by SNMP' template and it works just fine on one of our test switches and picks up all we need to see [for now]. However, when applied to one of our test routers, a Cisco C8500L-8S4X, it doesn't see the environmental bits e.g. PSU, Fans and Temperature.

Next, I looked at what the template was looking at, via Data Collection > Hosts > Items > SNMP walks PSUs - and I can see it has two OID's:

A quick SNMP walk later reveals neither of these OIDs exist. So I found one: 1.3.6.1.2.1.47.1.1.1.1.2,1.3.6.1.2.1.47.1.1.1.1.13 and added that in.

Now, under Latest Data for the host, I can see this:


There is also a 2nd PSU on 1.3.6.1.2.1.47.1.1.1.1.2,1.3.6.1.2.1.47.1.1.1.1.13 .23 but is off the bottom of the screen grab.

So far so good, but what I can't work out, for now at least, is how to "view the PSU statuses". And this is where I'm probably using the wrong words but, I think I need to use a discovery rule or do some pre-processing to include the PSUs so that we can see their status via a graph, alert on them, etc...

I've tried asking ChatGPT - how unhelpful was that but equally that could be my prompt. I've tried to reverse walk through how it does this for the switches, but am just getting lost and ... well, here I am.

So please, any thoughts on how I see the 2 PSUs, their status, etc?

FWIW: I've got "Zabbix 7 IT Infrastructure Monitoring Cookbook" arriving tomorrow and I'm booked on the 'Zabbix Certified Specialist' course but it's not until May.

[StuartD]

IMO - and who am I in the grand scheme - this zero response is why Zabbix doesn't get the traction it could do. I simply don't believe I'm the only one needing to do this? Ah well, I am trying.

[cyber]

This is USER forum, not ask devs anything forum... Yea, they lurk around, but it is no way their daily duty to scan all questions here and find answers...
Same is with other users, If I dont know the answer, I'm not going to answer... I do not have good terms with SNMP, so I try not poke it.. even with a long stick...
Not everyone lurks here every day, and probably skips reading all posts from last visit... So not answering happens...

But you are on right track with discovery. You need to walk the walk and use that info to construct items/triggers for all PSU-s that you may have there.. I guess you have that book by now and courses went well??

[StuartD]

Appreciate the response... I was airing my frustration I guess and perhaps I shouldn't have, but then my life is just a bit sh%^&* at present! So apologies if any offence taken by anyone.

I do have the book, but it hasn't helped in this instance and the course was good* but sadly brushed or rushed over the SNMP side of things. I even stopped the tutor to ask, and his response was akin to yours that he doesn't know or understand SNMP 'but it should work' was not useful Beyond that, he came back after lunch and said he'd spoken with a colleague who recommended we go on the "Zabbix SNMP monitoring" course. Can't see my company also paying for that.

* I'd even say it was excellent if you were a. going for the exam and/or b. working on supporting the backend of Zabbix. Neither of which apply to me.

[kz3]

This is my first post in the Zabbix forums, so I hope it helps someone.

As far as I know, OIDs are structured hierarchically. For example, the OID:
.1.3.6.1.4.1.2606.7.4.2.2.1.10.3.3
is for a CMC III device. Doing an SNMP walk like this:
snmpwalk -v2c -c communityname ip oid
returns a value like:
SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.3 = STRING: "0.00 degree C"
If you need more data, you can remove the last number from the OID:
snmpwalk -v2c -c communityname ip .1.3.6.1.4.1.2606.7.4.2.2.1.10.3
Now it returns multiple entries:
SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.1 = STRING: "Temperatura" SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.2 = STRING: "31.40 degree C" SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.3 = STRING: "0.00 degree C" SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.4 = STRING: "40.00 degree C" SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.5 = STRING: "35.00 degree C" SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.6 = STRING: "15.00 degree C" SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.7 = STRING: "10.00 degree C" SNMPv2-SMI::enterprises.2606.7.4.2.2.1.10.3.8 = STRING: "0.00 %"
This is especially useful for temperature OIDs, where you may have multiple values. You can later compare them for monitoring purposes.

---

Tip for Stuart's OID example:
1.3.6.1.2.1.47.1.1.1.1.2 1.3.6.1.2.1.47.1.1.1.1.13
I recommend retrieving data by changing the last numbers of the OID, like:
1.3.6.1.2.1.47.1.1.1.1.2 1.3.6.1.2.1.47.1.1.1.1
This way, it will show the entire subtree, not just the data behind a single OID like .1.1.1.1.13. Once you retrieve it, you can match the numbers and use them to create Zabbix items.
zz0.yrtnb1phwkbzz
1.3.6.1.2.1.47.1.1.1.1.2,1.3.6.1.2.1.47.1.1.1.1.13 this is Stuart`s oid
i recomend to start retrieving data changing the last numbers of the oid like

1.3.6.1.2.1.47.1.1.1.1.2,1.3.6.1.2.1.47.1.1.1.1 this way it will show the entire tree and not just the data behing number 1.1.1.1.13
once you retrieve it by comparing and looking for matching numbers you can add them like items

i needed to transalate (spanish user )whit chatgpt but the idea is the same

[jtnfoley]

kz3 gives good advice - truncate the OID string one .number at a time and walk back up the hierarchy so you can see subtrees. Building on that, sometimes walking back TWO subtrees will show something amazingly useful:
Look for a correlation between description strings and the value in a different subtree! Very often there will be xx.xx.xx.xx.xx.YY.1 = "PS 1 Line Voltage" and xx.xx.xx.xx.xx.ZZ.1 = "230.3" - (the Line Voltage of Power Supply #1 = 230.3 VAC)

That is, I've seen a LOT of instances where there's a descriptions subtree ("YY" in this example) and a values subtree ("ZZ") with the same final .number (.1) being the same, made obvious by walking back TWO subtrees. I hope I've explained that well enough!

Another thing I found helpful when diagnosing templates was to get all the related MIBs and feed them to snmpwalk with it's command line option and then grepping for interesting strings.

[cyber]

Feed your MIB-s to MIB browser, it helps to read them a lot..

[StuartD]

Hey all - I do appreciate the responses, and it looks like I need to be clearer.

I understand MIB structures and how OIDs work but what I need to do is understand how to use an OID so that I can do a discovery walk in Zabbix as I am clearly getting that aspect of it wrong. Put it another way, I have the right parent OID, what do I need to add to get the sub-components of said OID discovered without having to add each OID individually for FAN1, FAN2, FAN3, etc?

If I'm approaching teh task wrong, then please tell me how I should discover that Node X has Y number of fans and please monitor them?