HP-UX System Administrator's Guide: Configuration Management
1. Determine the status of the system.
Is the system still up? If not, you’ve probably found your problem. You will need
to reboot the system.
Is the system in single user state? If so, the only active terminal will be the system
console. Other terminals will not respond. You will need to switch to a multiuser
state. See the init(1M) manpage for more information on changing run states.
NOTE: To determine the run state of your system (from a working terminal),
enter:
$ who -r
The output will look something like:
. run-level 3 Jun 3 22:25 3 0 S
The current state of the machine is in the field immediately to the right of the time
(third field from the right). For complete information on each of the fields, consult
the who(1) manpage.
2. Determine if an editor is running on the terminal.
This is best done from another terminal. Issue the command:
$ ps -ft terminal
This displays all processes associated with the terminal with which you are
having problems. For each entry, check in the column marked COMMAND to see if
the process represented by that entry is an editor.
If you find that an editor is running at the terminal, it is probably in a text-entry
mode. You will need to save the work and exit the editor. For directions on how
to do this, consult the manpage for the appropriate editor.
CAUTION: If you are not sure of the status of the work being edited, DO NOT
simply save the file and exit. You will overwrite the previous contents of the file
with unknown text. Save the work in progress to a temporary file so that both the
original and edited versions of the file are accessible.
3. Enter Ctrl-Q at the terminal keyboard.
Terminals frequently use the start/stop (XON/XOFF) protocol to start and stop
output to them. stop is usually defined as Ctrl-S (XOFF) and start as Ctrl-Q
(XON). If output to the terminal was stopped because a stop signal was sent from
the terminal to the computer, it can be restarted by sending the computer a start
signal (for example, type Ctrl-Q from the problem terminal’s keyboard). Sending
the start signal does not harm anything even if no stop signal was previously
sent.
146 Configuring Peripherals