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Voice switchport changes - urgent

John Blakley
VIP Alumni
VIP Alumni

All,

With the current config on a switchport:

interface FastEthernet0/1

switchport mode access

switchport voice vlan 10

no ip address

no mdix auto

spanning-tree portfast

I need to change this to a trunked port because I'll be adding more vlans to this switch. If I do, will it screw anything up with the voice side? They run Cisco IP phones, but a vendor set them up and I know nothing about them.

Thanks,

John

HTH, John *** Please rate all useful posts ***
8 Replies 8

Yudong Wu
Level 7
Level 7

should not.

The packet from Cisco IP phone is dot1q tagged. Therefore, as long as you use dot1q as encapsulation on the trunk, it should work.

By the way, I did not see QoS is eabled under the interface.

No, that's the complete config for the switchport. When I'm done with it, it will be like

interface FastEthernet0/1

switchport mode trunk

switchport trunk allowed vlan 1,150,151

switchport voice vlan 10

no ip address

no mdix auto

spanning-tree portfast

I'm assuming that the "switchport mode access" is for data only, and the switchport voice is only for voice.

Thanks,

John

HTH, John *** Please rate all useful posts ***

You need add vlan 10 in allowed vlan.

Okay, thanks!

HTH, John *** Please rate all useful posts ***

kwu2 is correct that you will need to add it to the trunk allowed.

However, you wont need the switchport voice vlan 10 on the interface. The switchport voice command is to inform phones that are plugged directly into the port to use that VLAN instead of the default access VLAN. Because this is a trunk, you won't be hooking up a phone to the interface=)

I also forgot to mention that I believe you are going to need to remove the spanning-tree portfast because that is a switchport access command and not a trunk command.

Here is exactly how we have our trunked ports configured for our VOIP environment excluding QoS:

interface GigabitEthernet0/1

switchport trunk encapsulation dot1q

switchport trunk native vlan 901

switchport trunk allowed vlan 401,501,901

end

Our 401 VLAN is standard data, our 501 VLAN is standard voice, and our 901 VLAN management VLAN

Here is the example of our access interface excluding QoS:

interface FastEthernet0/1

switchport access vlan 401

switchport mode access

switchport voice vlan 501

spanning-tree portfast

end

Well, I'm a little concerned because I went ahead and configured the port for the access point to make sure I wouldn't lose connection. I started a continuous ping to the ap, changed the port to trunk, allowed vlan 1,150 on the trunk, and I lost a few packets (about 6). I'm HOPING that this won't bring the phones down that are connected into that switch when I move the port over to a trunked port. =)

Thanks!

John

HTH, John *** Please rate all useful posts ***

You need to setup the trunk to allow all VLAN's that you use on the switch. So, if your Fa0/1 is going to be your trunk port and you are using VLAN's 1, 10, 150 and 151 than your config should look like this:

interface FastEthernet0/1

switchport mode trunk

switchport trunk allowed vlan 1,10,150,151

no ip address

no mdix auto

Now you mention something about an AP? How is that fitting in with this trunk that you are trying to configure?

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