Administrator's Manual D. Recovering the Phone
Version 3.4.3 219 400HD Series IP Phones
D Recovering the Phone
If the phone is powered off for some reason during the firmware upgrade process, the phone
becomes unusable. This appendix shows how to recover the phone.
The recovery process is also available when the phone is connected to a VLAN.
To recover the phone, follow this procedure:
1. Identify that the phone is in recovery mode (see below)
2. Recover the phone (see below)
3. Verify that the phone downloaded the image file (see below)
D.1 Identifying that the Phone is in Recovery Mode
Network administrators can identify when the phone is in recovery mode.
To identify when the phone is in recovery mode:
Observe the following displayed on the phone's screen:
Figure D-1: Identifying Recovery Mode
-OR-
Observe that the phone reboots every +-5 seconds.
-OR-
You’ll receive a notification notifying you (users and network administrators) that the
phone has entered recovery mode. All phone models support this notification.
D.2 Verifying that the Phone is in Recovery Mode
Network administrators can verify that the phone is in recovery mode.
To verify that the phone is in recovery mode:
1. Connect the phone to the PC and run WireShark.
2. In WireShark, filter by bootp and then check if the phone is requesting Option 66 (TFTP
Server) & Option 67 (Bootfile) under Option 55 in the ‘DHCP Discover’ message, as
shown in the figures below.