Not a system admin (electrical eng so I develop ASIC's) and I've come across an issue where I need to understand switching better.
I have one device (A) that has pre tagged traffic coming out of it and I have two devices (B & C) that will be sending untagged traffic.
I want device A to be able to send some of its tagged traffic to B and send other traffic on another tag to C.
Lets say A sends out the tag 10 and 20.
So how I see this is I would set up the switch to have the port A is on be a tagged port on both VLAN 10 and 20, while B and C would be untagged ports each being on 10 or 20.
Let me know if that's wrong, but my question with this setup is, does the switch know to strip the VLAN tag before it hits device B and C, does it know to add a VLAN tag to the Packets coming from B and C? If this is the case, does this VLAN tag get stripped before reaching device A?
Some of the explanations on the web seem really contradictory.
An example switch I have access to is an extreme networks switch.