Info

This article describes best practice to provide a second extension to a phone. The same configuration parameters could be used to get even more accounts to register on a single phone.

Many SIP phones can have multiple accounts attached to a single device. You may also use this configuration to register an extension on a different domain, or even a totally different platform. 

Users will need to get used to seeing and selecting the correct line appearance to utilize this feature correctly.

Automatic Configuration

From the PBX Manager ensure each extension you want to be set up on a single device has a phone configured and no MACs are assigned. Each user configuration should look like this: 

Then click on:

1. Phones
2. Add Phone
3. Enter the Model, MAC, Preferred Server, and add each user one at a time to the Line X field.
4. Press Save

You'll see that the button configuration will have each user on each key in descending order as configured on the MAC. 

Note: The phone will preferentially use Line Key 1 as the primary extension on the device (if you lift the handset or press the speaker button it will automatically select line 1). Users must select their line key before picking up the handset to dial out from the configured extension. 

Manual Configuration

Manual configuration may be required if the phone(s) are in different domains or on another platform.

Yealink

Requirements:

You will need to have an available unregistered SIP device/credentials built in the user's phone tab.

This configuration will give you the ability to have two registered extension on a single device (even if they're on different domains).

The second extension on a phone will need to be manually provisioned via phone config (overrides). 

account.2.enable="1"
account.2.label="EXTNUMBER"
account.2.display_name="NAMEOFUSER"
account.2.auth_name="EXTNUMBER"
account.2.user_name="EXTNUMBER"
account.2.password="SIPPASSWORD"
account.2.sip_server.1.address="DOMAINNAME"
account.2.sip_server.2.address="%NULL%"
account.2.sip_server.1.port="0"
account.2.sip_server.1.transport_type="3"
account.2.outbound_proxy_enable="1"
account.2.outbound_proxy.1.address="usc.interactive.tel" 
account.2.outbound_proxy.2.address="%NULL%"
account.2.outbound_proxy.1.port="5080"
account.2.transport"0"
account.2.sip_server.1.transport_type="0"
account.2.sip_server.2.transport_type="0"
account.2.naptr_build="0"

Ensure to change the values of EXTNUMBER, NAMEOFUSER, SIPPASSWORD, and DOMAINNAME prior to applying the configs. You may also consider changing the proxy server to be geographically correct to the domain (USW, USC, or USE).

After adding overrides to the device config, you will have to auto-provision the device. You could also consider giving- the phone line keys to get dial tone on the second extension with the following overrides: 

linekey.X.line="2"
linekey.X.type="15"
linekey.X.value="0"

X indicates which linekey you want to add the configuration to. If you wanted it to be on the 3rd key down on the left you would put 3 in place of X:

linekey.3.line="2"

You can also refer to the Yealink Administrator Guide (Phone Customization > DSS Keys > Line Keys) to add BLFs, Speed Dials, or other linekey configs.

Example config to put a Park Key on the second account on key 9 on the phone.: 

linekey.9.label="Park 720"
linekey.9.line="2"
linekey.9.type="10"
linekey.9.value="720"

Polycom

Requirements:

You will need to have an available unregistered SIP device/credentials built in the user's phone tab.

This configuration will give you the ability to have two registered extension on a single device (even if they're on different domains).

The second extension on a phone will need to be manually provisioned via phone config (overrides): 

reg.2.address="EXTNUMBER" 
reg.2.displayName="NAMEOFUSER" 
reg.2.label="EXTNUMBER" 
reg.2.type="private" 
reg.2.auth.password="SIPPASSWORD" 
reg.2.auth.userId="EXTNUMBER" 
reg.2.server.1.address="DOMAINNAME" 
reg.2.server.1.port="5080" 
reg.2.server.1.register="1" 
reg.2.server.1.transport="UDPOnly" 
reg.2.server.2.port="5080" 
reg.2.server.2.transport="UDPOnly" 
reg.2.server.3.transport="UDPOnly" 
reg.2.outboundProxy.address="usc.interactive.tel" 
reg.2.outboundProxy.port="5080" 
reg.2.outboundProxy.transport="UDPOnly" 

Ensure to change the values of EXTNUMBER, NAMEOFUSER, SIPPASSWORD, and DOMAINNAME prior to applying the configs. You may also consider changing the proxy server to be geographically correct to the domain (USW, USC, or USE).

After adding overrides to the device config, you will have to auto-provision the device. You could also consider giving- the phone line keys to get dial tone on the second extension with the following overrides: 

lineKey.reassignment.enabled="1" 
lineKey.x.category="Line" 
lineKey.x.index="2"

X indicates which linekey you want to add the configuration to. If you wanted it to be on the 3rd key down on the left you would put 3 in place of X.