Recovery Strategy - IBM 265 Service Manual

Consult your modem manual for its specific response scheme for the &Dn command.
Two strategies are available for dealing with the modem's response to DTR:
v Recovery
v Prevention
Before you use one of these strategies, determine if your server's modem is set up
correctly to respond to DTR.
With the remote terminal connected to serial port 1 and defined as the Primary Console
Device, there are two tests you can perform:
1. Will the modem drop the connection after the System initialization complete
message displays at the remote terminal?
If Yes, the modem is set up correctly.
If No, try another &Dn setting for your server's modem. See your modem manual
for this information. The &Dn command appears in three places each in three of the
sample modem configuration files, as follows:
2. Will the server's modem disconnect when the power drops? You can make this
observation at the remote terminal by commanding your server to shut down and
power off. (Use the AIX command shutdown -F.) Watch for the message NO
CARRIER on your remote terminal.
If Yes, this is the correct response. The modem is set up correctly.
If No, try another &Dn setting for your server's modem. See your model manual for
this information. The &Dn command appears in three places each in three of the
sample modem configuration files. Only the following sample modem configuration
files contain the &Dn command (in three places each):
v modem_f.cfg
v modem_f0.cfg
v modem_f1.cfg
If you are using modem_z.cfg or modem_z0.cfg, you cannot control DTR response.
If your remote terminal does not disconnect after logging off, you must command
the remote terminal emulator to hang up. This then breaks the connection.

Recovery Strategy

The recovery strategy consists of making two calls to establish a remote session. This
solution is the easiest to implement and allows more freedom for configuring your
server's serial ports.
To set up a remote terminal session, dial into the service processor and start the
system. After the operating system is loaded and initialized, the connection will be
dropped. At this point, call the server back and the operating system will answer and
offer you the login prompt.
Appendix D. Modem Configurations
319