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PC Port VLan Configuration

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ichdurfte

Technical User
Nov 17, 2008
3
US
I have about 150 Cisco 7940 Series IP Phones, and I have all of them on their own VLAN(3). All of our computer systems are on VLAN(1), by default, either through the PC Port on the back of the phones, or various Ethernet jacks around the building.

I'm trying to separate our upstairs and downstairs machines, by putting the machines upstairs on a new VLAN(2), but I can't figure out how to change the PC Port on the back of the Cisco Phones to a different VLAN than the default.

I don't want to change the phones VLAN(3), I just want the computer to change to VLAN(2).

Is this possible, and where would I change it? I've checked Call Manager and the phone settings, but I can't seem to figure it out.

Thanks in advance.
 
I'm using Call Manager 4.1 by the way.

Thanks in advance.
 
This is done on the switches, not inside CallManager.
On the ports by default have a VLAN 1 for data. You can't see it but it kind of reads
'switchport access VLAN 1'

So to change that to VLAN 2 put in the command
'interface fastethernet 0/X'
'switchport access VLAN 2'
You'll be able to see the command. Depending on the switch, you may be able to do a range
'interface range fastethernet 0/X - X' to do a range of ports all at once.

I am assuming your switches are Cisco and that you have them set up like:
'switchport mode access'
'switchport voice vlan 3'
 
Err.. no. If there's a phone and a PC on each port, they better be set up as:

fastethernet 0/1
switchport mode trunk


And to control which vlan is used for voice and which for data, you would enter

fastethernet 0/1
switchport voice vlan 3
switchport trunk native vlan 2

That says "if it's a phone, assign it to vlan 3, if there's something else trunking on the port that something is in vlan 2.

 
Thanks guys. I'm going to change it sometime later this week. I'll post back and let you know how it goes.
 
Cisco no longer recommends that you set up the port as a trunk. Orignally they did.
When you put the command "switchport voice vlan 3" the switchport configured as 'access' it knows that there will be 2 VLAN's on the port, 1 data 1 voice, as long as the port is connected to a Cisco phone.
Security is the reason. If you set the port up as a trunk, someone can plug in a device acting as a trunk and get access to ALL your VLAN traffic.
Also, since you aren't trunking, you do not need to add the 'native vlan 2'.
The configuration I gave is per Cisco best practices. If you look up the SRND on CCO you'll find the information there.
It will work either way but I would suggest you configure per Cisco's best practices.
 
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