Help with Vlan Tagging

I posted this yestarday and can’t find it now so forgive me if there is a double post, but I’m trying to figure out how to setup a routerboard as a vlan tagger. Basically I have a router connected to our network through a Moto PTP backhaul that feeds into a switch that feeds a million other backhauls and switches, etc. The backhaul coming into that switch needs to get tagged as vlan2 so I can get their dhcp server segragated from the rest of the network. This router is not in my control so what I’d like to do is use a router board between their backhaul and my switch that takes all traffic and tags it as vlan 2 as it goes into my switch. I could probably do this with the switch but I need to get more familiar with these microtiks as we have them deployed everywhere.

I tried creating a bridge between the 2 ports and vlaning the bridge but it wouldn’t pass data. i’m guessing because there is no vlan2 yet on the backhaul side. Can someone point me in the right direction here? Is there a good rightup or does somone have some time to walk me through this? It seems like it should be simple enough but I’m missing a step somewhere.

Thanks

If I understood correctly untagged packets are coming in and you want so that those packets are leaving router tagged?
If so then it is quite simple

/interface vlan add name=vlan1 vlan-id=10 disabled=no interface=ether2
/interface bridge add name=bridge1
/interface bridge port
add bridge=bridge1 interface=ether1
add bridge=bridge1 interface=vlan1

Where ether1 is incoming interface (untagged packets)
ether2 outgoing tagged packets