For a variety of security and performance reasons, it may be desireable to host SIP handsets on a virtual LAN.
In order to configure a managed SIP device to reside on a VLAN, a VLAN interface needs be configured.
In order for the DHCP server on the VLAN interface to provide DHCP to the handset, the phone needs first to be configured to connect to the VLAN. This can be easily achieved by configuring DHCP server on both the physical interface and the VLAN.
Connect your handset to the physical LAN port (most likely through a switch) and power up the phone.
Ensure that auto-detection of hardware is enabled, and add the handset from detected devices.
On booting, the phone will initially receive a DHCP adddress from the DHCP server on the physical LAN interface. Click accept, but do not apply.
Before applying the configuration of the handset, edit the associated LAN interface and select the VLAN interface from the drop down list. Accept and Review/Apply.
Note:The drop down list is not visible when adding the handset. You will need to first accept the handset configuration, then right-click and edit the hardware entry before the other interfaces become available for selection
The phone should then detect the changes to it’s network settings and reboot itself, if this does not happen automatically, reset the handset to factory default settings from the GUI. On reboot, the phone will retrieve it’s updated configuration.
Note: Upon the phone booting, the review/apply button on the GUI may become bold. If this occurs, REVERT your configuration, to update the IP address field on the managed SIP phone. Only apply from the review/apply button once the managed SIP phone shows both the correct VLAN interface and IP address.
<Figure79-Hardware device residing on VLan>
Note: With certain handsets, the DHCP settings remain set until the interface goes down, so it may be necessary to physically remove and replace the network cable, or induce a power break cycle before the phone reconfigures itself to the VLAN.
If it is not feasible to enable DHCP server on the physical LAN (e.g. because of another DHCP server on the LAN), the phone must be manually pre-configured to attach to the VLAN so that it can receive its IP address and auto provisioning information from the DHCP server on the VLAN.