Error:snmp_new_v3_session:Unsupported authentication protocol(SHA256)

[agvineeth]

Environment:

App::Netdisco | 2.067002 SNMP::Info | 3.95 Net-SNMP | 5.9 (Also tried with 5.8) Netdisco MIBS version | 4.037

Build:

Netdisco Application is set up on a centos:8 base

SNMP Credentials config mode:

Multiple SNMP auth credentials are configured in netdisco/deployment.yml file and when trying to discover a device (configured to work with SNMP V3 using SHA256/AES256), netdisco discovery fails

Debug Error Log:

try_connect with v: 3, t: 3, r: 2, class: SNMP::Info::Layer3::Arista, comm: v3::SHA256/AES256 error:snmp_new_v3_session:Unsupported authentication protocol(SHA256)

Other details:

1. snmpget -v 3 and other snmp commands for the same device using SHA256/AES256 returned successful results
2. Also, this seems to a generic issue, not vendor specific. The debug error log copied is for an Arista device, I experienced the same with Cisco and other devices.

Any advise on how to get this working would be greatly appreciated. Thank you very much!

[ollyg]

Hi @agvineeth

I wonder if this is an issue with the build of net-snmp libraries on CENTOS 8. I see you tested against other device vendors but are you able to test other operating systems for the server end?

Alternatively you can install a different net-snmp library using the command below which might help:

~/bin/localenv cpanm --notest Alien::SNMP

[agvineeth]

Hello @ollyg

Thank you very much for your response :)

I tried the Alien::SNMP library and with that, I no longer see the Unsupported Authentication Protocol(SHA256) but now netdisco is is complaining about Unsupported privacy protocol(AES256) {Detailed error copied below}. Any recommendations?

P.S: I didn't fully understand what you meant by "but are you able to test other operating systems for the server end?". Could you please explain if its still relevant.

Thank you!

Error:

try_connect with v: 3, t: 3, r: 2, class: SNMP::Info, comm: v3:ogr:SHA256/AES256
error:snmp_new_v3_session:Unsupported privacy protocol(AES256)
unable to create session at /netdisco/perl5/lib/perl5/x86_64-linux-thread-multi/SNMP.pm line 620.
SNMP::Info::new() Net-SNMP session creation failed completely. at /netdisco/perl5/lib/perl5/App/Netdisco/Transport/SNMP.pm line 277.

[agvineeth]

Hello @ollyg When you get a chance. Could you please advise? Thanks!

[ollyg]

Hi @agvineeth I have released a new version of Alien::SNMP which should enable AES256 in the build. Please can you try running the same "cpanm" command again to upgrade it, and test again?

[agvineeth]

Good morning @ollyg! Thank you very much for helping us out here. I got a good news and a bad news.

Good news - I no longer see the Unsupported Protocol error Bad News - I am now facing a issue similar to one that you resolved a few years ago (SNMPv3 multi config issue - Copied the link below)

When running netdisco discovery command, the discovery is successful only if the SNMP credentials are at the top in the multi config YML. Otherwise the discovery fails. Please advise. Thank you!

https://github.com/netdisco/netdisco/issues/286

[ollyg]

Hi!

Thanks for the update and I’m glad progress is being made :)

The only solution to the multi config issue is to use “only” and “no” ACL option in the auth config so it is restricted to the relevant devices. Then netdisco will skip and go straight for the correct auth config.

This is a problem with net-snmp I cannot work around, sorry :)

Oliver.

On Mon, 27 Nov 2023 at 16:15, agvineeth @.***> wrote:

Good morning @ollyg https://github.com/ollyg! Thank you very much for helping us out here. I got a good news and a bad news.

Good news - I no longer see the Unsupported Protocol error Bad News - I am now facing a issue similar to one that you resolved a few years ago (SNMPv3 multi config issue - Copied the link below)

When running netdisco discovery command, the discovery is successful only if the SNMP credentials are at the top in the multi config YML. Otherwise the discovery fails. Please advise. Thank you!

netdisco/netdisco#286 https://github.com/netdisco/netdisco/issues/286

— Reply to this email directly, view it on GitHub https://github.com/netdisco/snmp-info/issues/504#issuecomment-1828156154, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAAHHVJR2J6JYCYX6WJVJA3YGS4CVAVCNFSM6AAAAAA6CVB3ROVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTQMRYGE2TMMJVGQ . You are receiving this because you were mentioned.Message ID: @.***>

[agvineeth]

Hello Olivier! Thank you very much for the recommendation. Sincerely appreciate all your time and efforts. We can close this case now. Good luck!