attaching a console when a system is up

[Eileen Millen]

We have a single console attached to several
HP systems through a linux system. Occasionally the console will not respond.
Is there a way to attach a vt console directly onto the system and have it respond when the system is up. We can do a factory reset when the system is down and get the console to work.
Or if we power off the system, the console wakes up and says that the system is being shutdown. It also doesn't work if we attach a console during bootup.

[Victor BERRIDGE]

Hi,
I know of a DEC aparatus, we have one in use but I cant remember the name and Im not on site at the moment, that let you connect multiple hosts using the serial connection, and let you connect via LAN by VT emulation on a pc or whatever you want (the DEC box has a IP addr.)

I can see what it is monday if you are interrested

Have a nice week-end
Best regards
Victor

[Bill Hassell]

Using another computer to act as a console is not the same thing as a real RS-232 terminal like the HP 700/92 terminal. Your Linux system is not a terminal but instead runs a terminal emulation program with all the perils of any serial port program.

While it would seem to be a simple task, serial ports can get locked up fairly easily and emulators are just that--imitations of the real thing. Just the simple mistake of listing a binary program on the screen can lockup most any emulator.

Most of the HP character mode programs are designed to work with HP terminals (and emulators) yet there are very few good HP terminal emuators for PCs. WRQ makes the best one (called Reflection for HP, not to be confused with Reflection/X which supplies Xwindows emulation plus a vt100 emulator).

You may also want to look at HP's web console product, a small box that converts a serial connection into a web page. It functions regardless of the state of the system aas it is an independent terminal interface.

[Tim Rotunda]

I connect all my serial console ports directly to a digiport terminal server (any terminal server should work) and can access them all from the LAN. It works great and takes very little setup on the terminal server. I can run everything I need to and if a reset is needed it is done simply via terminal server access. I believe it is the cheaper alternative to the web console and, I think, works better.
TR.a

[Eileen Millen]

If the linux console is locked up, is there anyway to put an HP console onto the system and get it to respond. Any special control sequence? Powering the system off works, but we wanted to avoid that if possible.

[Volker Borowski]

Hello Eileen,
the basic RS232 Protocol of the HP colsole is a three-wired XON/XOFF (I checked my cables, only 3 pins show up). So you might get your session XOFFed, by simply pressing Ctrl-s (which is XOFF).
This is the message from the terminal to the server to stop sending data.
Pressing Ctrl-q(XON) tells the server to continue.
If you configured something diffrent on your consoleport, like hardwired handshake or so, it might be your linux box cutting off the connection. May be it thinks of a modem-connection and drops DSR or DTR after a certain inactivity timeout ? This leads to the server thinking the console is no longer connected, so why send data ?

Do not know if this helps.
Good hunting
Volker