[FAQ] Utilizing VLAN's with Polycom phones

[SteffenBaierUK]

Polycom phones have the ability to utilize VLAN's

Note: If CDP or LLDP is active on a Switchport the DHCP VLAN discovery will not be used!

For a more detailed information about the network please check => here <=

An extract from the UCS 4.0.1 Admin Guide page 366:

To assign a VLAN ID to a phone using DHCP:

In the DHCP menu of the Main setup menu, set VLAN Discovery to Fixed or Custom.

• When set to Fixed, the phone will examine DHCP options 128,144, 157 and 191 (in that order) for a valid DVD string.
• When set to Custom, a value set in the VLAN ID Option will be examined for a valid DVD string.

DVD string in the DHCP option must meet the following conditions to be valid:

• Must start with “VLAN-A=” (case-sensitive)
• Must contain at least one valid ID
• VLAN IDs range from 0 to 4095
• Each VLAN ID must be separated by a “+” character
• The string must be terminated by a semi colon “;”
• All characters after the semi colon “;” will be ignored
• There must be no white space before the semi colon “;”
• VLAN IDs may be decimal, hex, or octal

The following DVD strings will result in the phone using VLAN 10:

VLAN-A=10;
VLAN-A=0x0a;
VLAN-A=012;

The Phone would as a factory setting utilize a fixed VLAN discovery

Step 1 Setting the VLAN Option via DHCP

Below example is from a Windows 2003 Server

Setting a predefined option:

  

Above Example shows how one of the predefined Polycom options 144 is added to the DHCP server.

 

The above example shows how the newly created predefined option is assigned to the scope with the data entry value as suggested in the admin guide.

VLAN 111 should be assigned via DHCP once the phone queries the Options.

Phone Factory Default:

A wireshark trace shows the Phone (factory default) sending in its DHCP Discovery

Option 55 queries 128, 144, 157 and 191 and the first Value will be used to set the VLAN ID.

VLAN Discovery Custom:

If the VLAN Discovery Menu has been set to Custom the phone will only query 129 within Option 55:

VLAN Discovery disabled:

If VLAN discovery is deactivated or CDP/LLDP is discovered the Phone will not query any pre-defined options:

Step 2 Setting/Changing VLAN Options on the phone

• Select the Menu Key

• Select Settings

• Select Advanced and add the Password (Standard would be 456)

• Select Administrator Settings

• Select Network Configuration

• Select Ethernet Menu 

• Select VLAN Menu 

The above example screen capture from a VVX500 shows the VLAN menu on a VVX500 within the Ethernet settings.

The same can be done using the Web Interface (UC Software 4.0.0 or later)

or using a configuration:

<disable device.set="1" 
 device.net.cdpEnabled.set="1" 
 device.net.cdpEnabled="0" 
 device.net.lldpEnabled.set="1" 
 device.net.lldpEnabled="0" />

Manual assignment of a VLAN via Configuration

Via your Provisioning Server, you can provision VLAN settings via the device.set parameters.

Example 1:

 The above example would set the DHCP VLAN Discovery to custom and to the customs value of 222.

Example 2:

<vlan device.set="1"device.dhcp.dhcpVlanDiscUseOpt.set="1" device.dhcp.dhcpVlanDiscUseOpt="Disabled" device.net.vlanId.set="1" device.net.vlanId="111"/>

 The above example would set the DHCP VLAN Discovery to disabled and set a fixed VLAN ID of 111.

Note: Please consult your Admin Guide for further details on the above!

Troubleshooting

The Phone sends in its initial DHCP Discover a request for Option 55 with the pre-defined sub Options:

DHCP Server is answering the DHCP Discover (Option 55 as factory default) with a DHCP Offer containing Option 128 for VLAN 111.

• Example Logging

Settings > Logging > Global Settings > Global Log Level Limit > Debug
Settings > Logging > Global Settings > Global Log Level Limit > Log File Size (Kbytes) > VVX/SPIP/SSIP prior to 5.5.0 = 180
Settings > Logging > Global Settings > Global Log Level Limit > Log File Size (Kbytes) > Trio 8300 & VVX after 5.5.0 = 1000
Settings > Logging > Global Settings > Global Log Level Limit > Log File Size (Kbytes) > Trio or CCX 10240
Settings > Logging > Module Log Level Limits > Configuration >  Event 3
Settings > Logging > Module Log Level Limits > CDP > Debug
Settings > Logging > Module Log Level Limits > LLDP > Debug
Settings > Logging > Module Log Level Limits > DHCP Client > Event 1

or via a configuration

<logging log.render.level="0"
	log.level.change.cfg="3"
	log.level.change.lldp="0"
	log.level.change.cdp="0"
	log.level.change.dhcpc="1"
	log.render.file.size.SSTRVOIP="1000"
	log.render.file.size.VVXD60="1000"
	log.render.file.size.VVX101="1000"
	log.render.file.size.VVX150="1000"
	log.render.file.size.VVX201="1000"
	log.render.file.size.VVX250="1000"
	log.render.file.size.VVX300="1000"
	log.render.file.size.VVX301="1000"
	log.render.file.size.VVX310="1000"
	log.render.file.size.VVX311="1000"
	log.render.file.size.VVX350="1000"
	log.render.file.size.VVX400="1000"
	log.render.file.size.VVX401="1000"
	log.render.file.size.VVX410="1000"
	log.render.file.size.VVX411="1000"
	log.render.file.size.VVX450="1000"
	log.render.file.size.VVX500="1000"
	log.render.file.size.VVX501="1000"
	log.render.file.size.VVX600="1000"
	log.render.file.size.VVX601="1000"
	log.render.file.size.VVX1500="1000"
	log.render.file.size.Trio8300="1000"
	log.render.file.size.Trio8800="10240"
	log.render.file.size.Trio8500="10240"
	log.render.file.size.TrioC60="10240"
	log.render.file.size.CCX400="10240"
	log.render.file.size.CCX500="10240"
	log.render.file.size.CCX505="10240"
	log.render.file.size.CCX600="10240"
	log.render.file.size.CCX700="10240"
	log.render.file.size="10240"/>

Results in this:

000015.486|cfg  |3|3014|RT|DHCP VLAN Discovery obtained VLAN list (VLAN-A=111;)
000015.486|cfg  |3|3014|RT|DHCP VLAN Discovery released initial DHCP lease.
000015.486|cfg  |3|3014|RT|Setting 802.1Q VLAN Id from LLDP/CDP.
000015.486|cfg  |3|3014|RT|Enabling 802.1Q tagging, VLAN Id = 111

• Example VVX600 UC Software 5.4.0

or

<logging log.level.change.cfg="3" log.level.change.dhcpc="3" />

Should show in the logs:

000023.054|dhcpc|3|00|dhcListener: Read succeeds: eth0 option: o-128 VLAN-A=111;.
000023.080|dhcpc|3|00|dhcListener: Read succeeds: eth0 state: BOUND.
000023.083|cfg  |3|00|RT|DHCP CfgRtMsgDhcpUp is received.
000023.084|cfg  |3|00|RT|DHCP VLAN Discovery obtained VLAN list (VLAN-A=111;)
....
....
000024.826|dhcpc|3|00|dhcListener: Read succeeds: eth0.111 state: PREINIT

Wireshark

The Phone would then release the DHCP IP from the native VLAN via a DHCP Release

And send a new DHCP Discover in the new VLAN 111

Depending on the Network card and operating system a registry change may be required to see tagged VLAN packets as explained => here <=