Help With 4500 VLAN configuration - tagged vs untagged

[scornflake]

Hello all,

At the risk of asking something that's been covered extensively, I'm still having trouble with this one, and I hope you'll bear with me.

I have a Cisco 1231AP access point that I have configured with two SSID's, each pointing to a different VLAN (I'll be getting to the 3Com switch part, I promise). Let's say that SSID 1 "Private" is on VLAN 1, and SSID 2, "Public" is on VLAN 3.

I need to get the one port that this AP plugs into on the 3Com 4500 to participate in BOTH VLANs, right? I've got ports 1-15 on the switch as VLAN1, and ports 17-48 on VLAN3. Port 16, that the AP connects to needs to be in both VLAN1 and VLAN3. The problem I seems to be running across, is which (if any) of these ports should be/need to be tagged?

since VLAN1 is the default VLAN, do I need to make VLAN2 (not yet in existance) that "private" network and VLAN3 the "public"? (in other words, does it mater that I'm trying to comingle VLAN1(native) and VLAN3? Would I be better off comingling VLAN2 and VLAN3, and leaving VLAN1 basically empty?
Also, does the port 16 (for the AP) need to be a hybrid (or trunk, or access)?
What would be most helpful would be a listing of what VLANs I should have, which ports should be in each, the type of those ports.

I really though I understood this, but I can only access the network when connecting to the "Private" (VLAN1) network via the SSID 1.

Thanks in advance.

 

[IRudebwoy]

Make port 16 a trunk (or hybrid) and a tagged member of the VLANs you want to use. Make sure your IPs are consistent with the VLANs you're attaching to.

Me personally, I would use another VLAN for your private and use the Default (VLAN 1) to manage the device.

But that's just me.

 

[blueshark101]

A little more detail for you scornflake...

All switches have by default 1 VLAN to which all ports belong (untagged) and not unreasonably that is called VLAN 1!

So the first thing to decide is which SSID goes where - having agreed that SSID 1 is in VLAN 1 (like the logic there) then you do NOT have to do anything more to the ports that are only going to need to access that network. So by default ports 1-15 are already in the correct VLAN.

If SSID 2 is in VLAN 3 then you need to make that the default VLAN for ports 17 to 48 - you do that by changing them to untagged ports in that VLAN - this will remove them from VLAN 1 and put them in VLAN 3.

Port 16 is a "special" port, as IRudebwoy suggests, this port needs to be in both VLANS to pass all the relevant traffic - to do this it needs to be untagged in VLAN 1 and Tagged in VLAN 3. You also need to ensure that the Cisco end of Port 16 is tagged in a similar way using the same VLAN numbers.

-Blue
The significant problems we face cannot be solved at the same level of thinking we were at when we created them