User guide

PTP 800 Series User Guide Using recovery mode
phn-2513_004v000 (Oct 2012)
7-71
Using recovery mode
This section describes how the CMU enters recovery mode and how to recover the CMU.
For a general description of the recovery mode, see Recovery mode on page 1-62.
When the CMU is in recovery mode, it cannot be recovered via a remote network
connection. It can only be recovered from a PC that is directly connected to the
Management port using the default IP address 169.254.1.1.
Entering recovery mode
When the CMU Modem LED (Table 5) blinks red, the CMU has entered recovery mode
automatically. The CMU may enter recovery mode automatically in the following
circumstances:
• When a checksum error occurs for the main application software image.
• When the Short Power Cycle for Recovery attribute is enabled (Table 232), the CMU is
power cycled and the “off” period is between one and five seconds.
To enter recovery mode manually, proceed as follows:
1
Power off the CMU.
2
Press the CMU front panel Recovery button (Figure 4).
3
Keep the Recovery button pressed while powering on the CMU. Keep the
Recovery button pressed for at least 20 seconds after powering on.
4
Wait until the CMU Modem LED blinks red, indicating that the CMU is in recovery
mode.
5
Proceed with recovery options, as described below.