MS120 and MS210 multicast bug on Fiber Port

[HieuPhan]

We deployed MS120 for a customer, which use MMF to inter-connect their building. Right after deployment, we found out that Multicast traffic have a problem traversing through building. After hours of troubleshooting, we finally get confirmation from Support that there is a known bug on MS120 Fiber port with multicast.

We took a step further and tested MS210, same bug.

MS225 is clean.

This is just FYI and hopefully this bug will be fixed soon.

[MilesMeraki]

Thanks for informing the community @HieuPhan

[PhilipDAth]

I believe this is resolved in the 10.16 code - but I have not tested this myself.

[HieuPhan]

hm... Thanks Philip. I just schedule upgrade for tonight. I'll let everyone knows tomorrow if it fixed.

[HieuPhan]

I confirm the latest Beta firmware do not fix this particular bug. Just have to wait for the next ones 🙂

[VictorC]

Hi Hieu,

There are currently no known bugs relating to Fiber ports and multicast. The MS210 is very similar to the MS225 (hence why they are stacking compatible), and if a bug exists on the MS210, it should also exist on the MS225. The only similarity between the MS120 and the MS210 is the 1G SFP ports. Are you currently testing the MS225 with the same SFP module you have used on the MS120 and MS210?

[HieuPhan]

hi Victor,

Yes, we are able to get MS225 to work with the same SFP. We just requested 3 MS225 trial  to fully deploy it, and will perform packet capture for MS225 and MS120 so Support team can compare and hopefully declare it's a bug soon.

I think this is specifically to the 1Gbps Fibert port itself, not the switch-build, since traffic works within copper ports (to multiple switches).

Hieu

[HieuPhan · Accepted solution]

Update to everyone:

It's not a BUG. IGMP Snooping was intercepting the packet flow. Disable IGMP Snooping resolved the issue