I will preface this by saying that I only have one SWOS device, so it's completely possible that this is user error.

I operate an IPv6 only network, and other than the IPv4 necessary to manage this SWOS device, all other hosts connected are absent of IPv4. There is a problem which I have seen on some other switches likely using the same chipset (Engenous stuff) where it appears to flood link layer and multicast traffic.

For example, I have 2 VLANs, tagged to the SWOS device. Three ports are configured for access layer (untagged) VLAN380, one is untagged 1204. On connected devices, I see IPv6 RA for every VLAN tagged to the uplink port as well as LLDP for select devices attached to VLANs not untagged on those ports. . Since Mikrotik does not allow for unicast RA in IPv6, I cannot test that it is not a multicast issue since IPv6 RA uses FF02::1, but i am definitely seeing Neighbor Discovery for all of the VLANs as if I am on one L2 segment.

This is broken behavior and causes all hosts to experience broken connectivity. I am hoping that this is an issue of me misconfiguring something, but there aren't exactly a lot of knobs in SWOS, so I am guessing this is actually a bug. Has anyone seen this? Solutions? Just replace this device?

nb

This ended up being too much of an issue and I replaced the CSS106 with an RB450. Mikrotik support - this is a problem you should address, assuming it is not a user error on my part. Given that I have seen it on other platforms, I suspect perhaps it may be a chipset or SDK limitation, but either way it's a fairly significant risk in that it can expose hosts on IPv6 networks that they are not intended to be on.

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