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[nov1ce]

Hi all-

Appreciate your assistance with the following VLAN question. Here is my setup:

[SW3] <-> [ROUTER] <-> [SW2] <-------> [SW1]

where:

[SW3] is Cisco Catalyst 3548 switch with 3 VLANs configured,

[ROUTER] is Cisco 2851 router with three subinterfaces configured in trunk mode (encapsulation dot1Q) and relevant routing, so three VLANs can talk to each other,

[SW2] is Cisco 6509 switch. It's not aware about VLANs on SW3 but has routing entries pointing to ROUTER.

[SW1] is Cisco 6509 switch interconnected with SW2. It's not aware about VLANs on SW3 but has routing entries pointing to ROUTER.

I need to assign several ports on SW1 and SW2 to be part of VLANs from SW3. Please advise how can I propogate VLANs from SW3 over ROUTER to SW1 and SW2? Can I somehow inject VLANs through ROUTER -- does it mean that "ROUTER to SW2" interface should be configured in trunk mode with requested VLANs to be distributed? I have no problems sharing VLANs between SW2 and SW1.

Thank you in advance.

[donjohnston]

You really can't since VLANs terminate at a layer 3 interface. There is a workaround (IRB), but it's pretty ugly.