IBM Enterprise Server S80, User Manual

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If yes, the modem is set up correctly.
If no, try another &Dn setting for your server’s modem. See your modem
documentation for this information. The &Dn command appears in three places
each in three of the sample modem configuration files, (see the note on page 224).
Note: 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 three calls to establish a remote session. This
is the easiest solution to implement, and allows more freedom for configuring your
server’s serial ports.
To set up a remote terminal session, dial in to the server and start the system. Wait 5
minutes for the initialization period and call again to gain control through the Service
Processor menus. Continue booting the system from the System Power Control menu.
After the operating system is loaded and initialized, the connection is dropped. At this
point, when you call the server back, the operating system answers and offers you the
login prompt.
Prevention Strategy
The disconnect is caused by the operating system when it initializes the primary
console. The tests listed above are conducted with the remote terminal selected as the
primary console to manifest the modem’s response to DTR transitions.
If a local ASCII terminal or a graphics console is to be a permanent part of your server,
make one of them the primary console. Your remote terminal will no longer experience
the connection loss.
If a local console is not a permanent part of your server, you can still assign either the
unused graphics console or the unused serial port as the primary console. This gives
you the desired seamless connection at your remote terminal.
If you choose to use the unused serial port as the primary console, some initialization
traffic will be sent to any serial device attached to that port. As a result, that serial
device’s connection and function could be affected. These impacts may make that port
unattractive for devices other than a temporary local ASCII terminal.
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S80 and S85 User’s Guide