KH1508 / KH1516 User Manual
50
Firmware Upgrade Recovery
There are basically four conditions that call for firmware upgrade recovery:
When the unit’s firmware becomes corrupted for some reason and you are
unable to operate it.
When you invoke Firmware Upgrade Mode (see
page 31), but decide not to proceed with the upgrade.
When a firmware upgrade procedure is interrupted.
When a firmware upgrade procedure fails.
To perform a firmware upgrade recovery, do the following:
1. Slide the
Firmware Upgrade Recovery Switch
Recover
position.
2. Power off and restart the switch according to the instructions given in the
Powering Off and Restarting
section (see page 19).
3. Repeat the upgrade procedure starting with
4. When the upgrade ends, power off the switch
5. Slide the
Firmware Upgrade Recovery Switch
back to the
Normal
position.
6. Repeat Step 2.
Note:
If one of the child units fails to upgrade successfully, unchain it from the
installation and perform the recovery and upgrade operation on it
independently. After it has been successfully upgraded, plug it back into
the chain
kh15816.book Page 50 Tuesday, November 27, 2007 1:05 PM