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VLAN Tagging confusion

Jason Biehl
Occasional Visitor

VLAN Tagging confusion

I am working on a fairly large implementation of Procurve switches. I am having some trouble finding a clear answer to the 'no untagged' command for VLAN 1.

Should the tagged (DOT1Q uplinks) be included in the 'no untagged' statement for VLAN 1. I see that when a Trunk is setup it is part of the 'no untagged' statement. Simply put should all ports be 'no untagged' on VLAN 1 if they are either untagged in another VLAN or part of a DOT1Q tag?

Thanks
1 REPLY
Jeff Carrell
Honored Contributor

Re: VLAN Tagging confusion

Jason asked: "Simply put should all ports be 'no untagged' on VLAN 1 if they are either untagged in another VLAN or part of a DOT1Q tag?"

simply, yes, (and you don't control that statement being made) unless a port is part of a trunk group as you noted above.

Some port/vlan basics:

1) all ports are untagged members of vlan1 by default. (of course you know this, but I wanted to put it all down)

***
2) when a port is untagged into a different vlan, there is an automatic config line added into vlan1 of the 'no untagged x'.
***

3) when you simply tag a port into a vlan without changing its untagged state, the port remains untagged in vlan1.

4) you cannot remove that 'no untagged x' line in vlan1.

5) all ports must have a vlan home, can be untagged at most in one vlan, can be tagged multiple times, can be tagged and untagged at same time - but not in same vlan. a port does not have to be untagged in any vlan, as long as it is tagged in at least one vlan (the gotta have a home mode).

6) when a port is added into a trunk, the port loses it "individuality", it is part of the trunk now.

hth...Jeff