Overlapping VLANs?


Jun 6, 2012
I'm working with a 3com baseline switch2948-sfp plus switch and I'm wondering if it is even possible to create overlapping VLANs.

Its setup page just has untagged, tagged, and not a member selections.

Certain departments only need to see 1 of the 4 fileservers to work from, but some of the management needs to see all 4 of them.

Is it possible to have a setup like this

Users are Ports 1-20 Servers are Ports 21-25

1,2,3,4 21, 25

5,6,7,8 22, 23, 25

9, 10, 21, 22, 23, 24, 25

11, 12 21, 24, 25

As you can see everyone needs server 25 and there is overlapping for the rest.
If you were to define your servers with tagged ports and define multiple virtual interfaces you could do this. You would for example create 4 interfaces for server 25.

Not a recommended design it tends to be pain to keep straight.

The more common design is to place all the servers in a different vlan and then use rules to restrict the traffic.