What happen to vlan tag info when passing through a router

[haluochen9988]

What happen to the vlan tag information when packet pass through a router? Will that tag info stripped off or still stay with the packet when switch on the other side receive the packet?

[Karsten Iwen · Accepted solution]

A VLAN is terminated by a router. So the router will strip off the tag, but if the outgoing interface is also a trunk, a new VLAN-tag can be created based on that VLAN. If the router-ingress interface is attached to an access-port of the switch, then of course the router won't see any VLAN-tag.

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[Joseph W. Doherty · Accepted solution]

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Posting

If traffic will actually be routed, i.e. a L3 hop, ingress Ethernet frame is dropped and egress Ethernet frame is new.  VLAN tag information would not carry over.