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Comms between vlans via router

This is all theory as I haven't got a router to test.
Looking at the attached /embedded drawing, PC1 needs to talk to PC2.
Switch 1 has ports 2-23 configured for Switchport mode access, ports 1 & 24 are trunks.
Switch 2 has ports 1-23 configured for switchport mode access, switchport access vlan 2, port 24 is trunk.

My question is, do the switches need to have both interface vlan 1 and interface vlan 2 configured in their config?, or does switch 1 only need interface vlan 1 as none of the ports will be used for vlan 2?
I currently have all switches configured with both.

Network Diagram
1 Solution
Niten KumarPrincipal Systems AdministratorCommented:
Yes the both the switches need interface vlan 1 and interface vlan 2 configured in their config because as the frames leave the switch a tag is inserted in the frame.  When an Ethernet frame traverses a trunk link, a special VLAN tag is added to the frame and sent across the trunk link.

As it arrives at the end of the trunk link the tag is removed and the frame is sent to the correct access link port according to the switch's table, so that the receiving end is unaware of any VLAN information.
Rick_PenneyAuthor Commented:
Excellent, I thought as much as I guess that's why VTP exists.
I'm very grateful for your quick reply and clear explanation
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