SNMPv3 Authentication issue with Truenas

[zuser33456]

Hello everyone! This is my first post on this forum and I am hoping that someone could help me with this issue I have been having. The long story short is that I am able to monitor a TrueNas server over SNMPv2, but whenever I try to monitor it over SNMPv3 it does not want to work. I have uploaded images of what I am looking at, but i have verified that all of the credentials match, and the network is most certainly reachable as it works with SNMPv2 but not 3. I am using DES for the time being for troubleshooting purposes, but it still does not seem to want to work. I am using Zabbix 6.0 LTS on Ubuntu 22.04, all packages are up to date on the zabbix side as well as truenas. Any ideas as to what could be happening here would be welcome. Thank you.

[EHRETic]

Hello,

Did you find any solution for it?

I also have trouble getting SNMPv3 to work with TrueNAS, despite having it working with multiple Synology and some other devices.

Thanks and kind regards
Franck

[cyber]

Any messages in logs? Can you turn on some debugging to see, what Zabbix is trying to do? It may create a lot of logs, if you have many SNMP items... tcpdump to capture some traffic and then wireshark to decrypt and analyze that?

[EHRETic]

Any messages in logs? Can you turn on some debugging to see, what Zabbix is trying to do? It may create a lot of logs, if you have many SNMP items... tcpdump to capture some traffic and then wireshark to decrypt and analyze that?

I could finally get it working with the following matching values (I could not get MD5 to work):

Authentication protocol:
Zabbix: SHA1
Truenas: SHA

Privacy protocol:
Zabix: AES128
Truenas: AES

This should be mentioned in template documentation because Truenas doc is very generic.
Hope this can help somebody

PS: thanks cyber ;-)

[cyber]

I could finally get it working with the following matching values (I could not get MD5 to work):

Authentication protocol:
Zabbix: SHA1
Truenas: SHA

Privacy protocol:
Zabix: AES128
Truenas: AES

Now if you say this... I suspect those md5 and des algorithms may be forbidden/disabled in recent linux versions (don't quote me on that.. )... It may have nothing to do with Zabbix here, but with your linux setup, which does not allow you to use those (for nowadays) unsecure algorithms.

[EHRETic]

Now if you say this... I suspect those md5 and des algorithms may be forbidden/disabled in recent linux versions.

Héhé, good point, it might be the case, Truenas Core is based on FreeBSD

[cyber]

Héhé, good point, it might be the case, Truenas Core is based on FreeBSD

I meant, truenas wants to use all that, but your Zabbix server side refuses as it considers all that a bit unsecure...

[EHRETic]

I meant, truenas wants to use all that, but your Zabbix server side refuses as it considers all that a bit unsecure...

I would say the opposite because I'm using it to monitor my Synology(s), so the Zabbix server accept it. No?

Or is there any "grandfather permission" to use it because I started using it when it was still there (like a cached credentials thing)?

[cyber]

Synology uses MD5 and DES? If that works, then its not really a Zabbix issue as I suspected.. But then again, why it would allow configure those on Truenas side, if they are considered bad on that side ..:P questions, questions... and no answers.

[EHRETic]

Synology uses MD5 and DES?

I use MD5 and AES128 and I tried the same on Truenas, didn't work.

questions, questions... and no answers.

Yes... it bothers me too!