SNMP Datatypes as Items

Setup, Configuration and Use Items & Sitemaps
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I’m running OH2.3 and I have the SNMP binding installed and working, and I’m starting to play with getting some items set up to monitor a few things on my network. However, I’m having issues with data types. If an item returns an integer or string, I’m fine - I just use number or string and I’m off. However, several things I’ve looked at have data types other than integer or string, specifically:

Counter32 - just a large integer (0 to 4294967295)
Hex-STRING - two digit hex string - 00 through ff although I’ve only seen numbers in testing with my device
Timeticks - non-negative integer (range is 0 to 2e32 - 1) - this is going to be the hardest to deal with as it’s designed to show a time duration in mS

With these, if I use number, I get “NULL” when displaying in my test page within habpanel. If I set them to string, I get “Null” when displaying in habpanel. The all caps version is consistent with something completely wrong with an item, IE not set up correctly. The “Null” makes me think it’s atleast trying, but can’t handle the data for some reason. Anyone have a solution/work-around for this?

I’m using snmpwalk on the same linux box as OH is installed on for testing, and it sees the data fine. Here’s a couple things I’m looking at:

danny@Server-Linux18:~$ snmpwalk -v1 -c string 192.168.xxx.xxx 1.3.6.1.4.1.41112.1.6.2.1.1.6
iso.3.6.1.4.1.41112.1.6.2.1.1.6.1 = Counter32: 3559486313
danny@Server-Linux18:~$
danny@Server-Linux18:~$ snmpwalk -v1 -c string 192.168.xxx.xxx 1.3.6.1.2.1.1.3
iso.3.6.1.2.1.1.3.0 = Timeticks: (743893) 2:03:58.93
danny@Server-Linux18:~$
danny@Server-Linux18:~$ snmpwalk -v1 -c string 192.168.xxx.xxx 1.3.6.1.4.1.11.2.3.9.4.2.3.3.5.1.2
iso.3.6.1.4.1.11.2.3.9.4.2.3.3.5.1.2.1 = Hex-STRING: 80
danny@Server-Linux18:~$

Additionally, I have a question about the SNMP binding information located at:

In the GET, it lists an “update” field. Most examples I’ve seen have it at 10000. What is this value exactly? I’m guessing it’s the time between polls in mS (so 10000 would be 10 sec), but I haven’t seen anything that actually says what it is…

Thanks,

Danny

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Instead of HABpanel, what does the log show?

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Well, the answer ended up being that I’m an idiot… Notice in the above that the returned value isn’t exactly the same as what was queried. I was missing the final digit on them. Added that, and they work - mostly…

For the datatypes I"m working with, here’s how you have to handle them:

Counter32 - Number or string works. Since it’s a number, I’m using Number.
Hex-STRING - will work with String or Number. Number cuts off the leading zero. I’m using string and handling it via rules, etc.
Timeticks - This requires String. And it gives the time in a format like: H:MM:SS:xx so you don’t even have to do anything with it (unless you just feel like it)…

Thanks,

Danny

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Forgot to mention an answer to my other question as well. The “update” is in mS. Set it to 1 and the changes were essentially instantaneous. Set it to 10000 and things updated every 10 sec.

Danny