I think ive nailed this one myself. Seems like an obscure Mikrotik issue. My original config had each of the 3 groups using their own master port, then each VLAN was applied to that master port. VLAN 200 would always work AOK, but packets form the router coming out of VLAN300 and VLAN400 ports had t...

Did you ever find a resolution to this? I am having a similar issue with not able to reach the router from a Linux host but windows is ok.

Ok, weired one here guys. Ok, so what I'm doing is splitting a CRS125-24G into 2 separate routers essentially. Some ports on VLAN300, some on VLAN400 then one on the "WAN" All works great, plug into one of the VLAN300 allocated ports and get an IP on that range no worries, plug into the VL...