SG300 VLANs for IP Phones?

[greg.kujawa]

I have a site with Polycom VVX IP phones. The users' computers patch into the back of the phones for data connectivity. Currently I have all endpoints as part of the same LAN segment. But we have a fair amount of UDP congestion, so I need to partition the phones and computers into two separate VLAN's.

I configured VLAN 11 on the SG300-28PP, and defined this VLAN as being allowed on each switch port. So we have the default untagged VLAN 1 and the tagged VLAN 11. Here is a snippet from that in the config:

!
interface vlan 11
name voip
!
interface gigabitethernet1
switchport trunk allowed vlan add 11
!
interface gigabitethernet2
switchport trunk allowed vlan add 11
!
interface gigabitethernet3
switchport trunk allowed vlan add 11
!

On the Polycom phones I configured them with a fixed VLAN 11 ,disabled VLAN discovery, and rebooted them. While the computers operated fine, the phones didn't appear to hit VLAN 11. I checked that CDP and LLDP were disabled on the phones. Still no luck. 

Next I went into the SG300 and configured Auto Voice VLAN as VLAN 11, enabled VLAN discovery, and enabled CDP and LLDP on the phones. Still came up empty. 

Next time I'm at this remote site I will try connecting with my laptop and manually assigning it VLAN 11 to see if that works. I've searched around and found a few posts and articles discussing these procedures. And have tried to implement accordingly. Any other suggestions? It's more likely a Polycom config issue than an SG300 config issue. But want to cover all angles!

[Giuseppe Larosa · Accepted solution]

Hello Greg,

in the following configuration guide for firmware 1.3.7 is mentioned another option

https://www.cisco.com/c/dam/en/us/td/docs/switches/lan/csbms/sf30x_sg30x/administration_guide/CLI_Nikola300_1_3_7.pdf?dtid=osscdc000283

on pag 562 section 33.1

voice vlan state {{auto-enabled | auto-triggered} [ipv6]} | oui-enabled | disabled]no voice vlan stateParameters•oui-enabled—Voice VLAN is of type OUI.

You should be able to use the first three bytes of the Polycom IP phones MAC addresses to specify the OUI that should trigger voice Vlan assignmnet using oui-enabled method.

To change the administrative state from oui-enabled to auto-enabled (or auto-triggered), or vice versa, you must first set the administrative state to disabled.

Hope to help

Giuseppe

[greg.kujawa]

Thanks for the specific info. I think the issue is on the Polycom phones and how they are configured. Once I get more time I will visit the remote site again and go through this. There are options on these phones to pull VLAN configs via discovery of DHCP options, define VLAN based on CDP/LLDP packets, or define VLAN in a fixed manner. Each of these options requires certain features to be either disabled and enabled on the switch. That combination was likely where I was running into issues!