VOSS stops responding to SNMP requests over Mgmt VLAN when a Mgmt CLIP is also configured

[Nicolas_Melay]

Hi all,

I have a bunch of VOSS devices running 8.10.2.0.
Inter VLAN routing is done outside of the fabric, so it's basically a L2 fabric, and switch mgmt is done over mgmt VLAN interface.
I'd still like to be able to configure an mgmt CLIP in case something goes wrong (something always goes wrong), and use it as alternate mgmt path, jumping from another switch.
Unfortunately, doing so (configuring an mgmt CLIP) breaks SNMP on the mgmt VLAN interface.

Is there some way to tell VOSS to answer back SNMP requests on the same interface they arrived, or at least configure which mgmt interface should handle SNMP requests, or will the mgmt CLIP always take over?

[Phil_]

Hi Nicolas,

maybe this will help you:

“Operational Notes for UDP Management Applications
Management applications that use UDP, such as TFTP, RADIUS dynamic server, or SNMP can have restrictions when multiple Segmented Management Instances are configured with overlapping or asymmetrical routing.

Note

The restrictions listed do not apply to TCP applications or if a single Management Instance is configured.
Asymmetrical routing can occur in any of the following scenarios. For the first two scenarios you can use the OOB or VLAN Management Instance IP address instead of the CLIP Management Instance IP address. Also, use FTP or SCP file transfer as an alternative because those protocols are TCP based.

In the third scenario, you can configure more specific static routes for networks originating UDP client communication to the OOB or VLAN Management Instance IP address if the CLIP Management Instances also configured.

1. Client communication to the CLIP Management Instance IP address is from the same subnet as the VLAN Management Instance

2. Client communication to the CLIP Management Instance IP address when specific static routes or default route with higher preference back to the client network exist on OOB Management Instance or VLAN Management Instance.

Segmented Management Operational Notes for UDP Management Applications
VOSS User Guide for version 8.6 81

3. Client communication to the OOB Management Instance IP address or VLAN Management Instance IP address that relies on a default route with a lower preference than the internal default route used by the CLIP Management Instance.

4. Client communication to the CLIP Management Instance IP address is from the same subnet as the OOB Management Instance (even if the OOB port is down).”

Best regards,
Phil