Using tip for Serial Terminal Access

The tip command can be used to allow one Unix workstation to act as a serial terminal for another Unix system. The following must be in place to allow this to work between two Sun systems:

The system to be observed should be halted. If a keyboard needs to be removed from the system, the system should be powered off. (Some older models will blow a keyboard fuse if the keyboard is removed while the system is powered up.)
The /etc/remote file on the observing machine needs to have the hardwire line pointing to the correct serial port. By default, the file points at port b. In this case, the line should look like:
:dv=/dev/term/b:br#9600:el=^C^S^Q^U^D:ie=%$:oe=^D:
If serial port a is to be used, change the line to look like:
:dv=/dev/term/a:br#9600:el=^C^S^Q^U^D:ie=%$:oe=^D:
A null modem cable should be run between serial port a on the system that is under observation and the serial port configured in the /etc/remote file's hardwire line on the observing system. (A null modem cable interchanges wires 2 and 3 on one end.)

On the observer system type "tip hardwire" in a window. (It is best to use a windowed environment so that control of the system can be regained in case of a session hang.) A "connected" message should be echoed to the window. If not, use admintool or another utility to see if the serial port is already in use.

A tip session should not be closed by killing the process, the shell, or rebooting the observer machine. In these cases a /var/spool/locks/LCK file may not be cleaned up properly, which may prevent further tip sessions.

Some common tip commands are:

~. (end session)
~# (break--same as STOP-A)
~? (list all tip commands)

(Other commands may be found on the

tip

man page.)

The system to be observed/controlled can be powered up. If the diag-switch? PROM environment variable is set to true, hardware diagnostic data will be displayed to the tip window. (See the Hardware Diagnostics page for further information.)
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