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Turning Your Mac Into a Serial Console Server
chrisbw writes "Want to put that old VT100 terminal to use? Mac OS X Hits has a story on how to make a couple simple changes in OS X to enable login on a serial terminal (even over a USB serial adapter if you're on a newer mac). Cool trick for adding a text-based web surfing or email terminal in another room, or remote iTunes control!"
Well, my point was that if you're on a newer Mac that doesn't have a serial port, that you can use a USB serial adapter and OS X will happily use it as a regular tty.
Chris -- http://www.bitter.net/
I think you've missed the point entirely.
:) (used to connect all your serial console machines togother)
This also goes in with the story being mis-named. One of the nicer things about having serial console access to your machine is you have the ability to do things like if you were directly at the console... I don't think you're going to drop your system to single user mode while using the network. Or, if you're configureing something, and you accidentally mess up network connectivity, its a very nice backup. Also, on real hardware like suns, you can send serial breaks over the line, get into firmware, and do what is necessary, whether it be synching the machine due to crash, or whatever.
This story is also missnamed.. a serial console server is a server with a lot of serial ports on it
Now, I'm not entirely sure what the use of a serial console is under osx, but the impression I'm getting is that its getting a bit more useful each revision of that OS. But under any other unix, not having a serial console in a production enviroment is just asking for trouble.
David
I just bought a second-hand iMac to replace the terminal next to my bed. I can now browse with Mozilla instead of Lynx, in bed, and have many good dreams afterwards :-)
-- Cheers!
Actually, it will run on almost anything, just it doesn't want to. What many people are doing nowadays is buying old clones and using XPostFacto (try versiontracker.com) to install OS X where it wouldn't normally go. Like on a UMAX clone with a G4 800Mhz upgrade card in it.
- Sherman
I'm not sure he's the one that missed the point.. A 486 has serial ports too.
Right, but this is just another chink in the argument that "we can't let you work on a mac because we still need x86 to do "
The more it takes on the functionality of a regular *nix (and the fewer handrolled apps your company has) the more likely you can use a mac, if that's what you prefer.
It would really be a story if you could do this without his knowledge. Hehehe... suddenly, Celine Dion plays through his speakers at top volume, and he can't turn it off....
There's always TopGunSSH . Its a old-school Palm SSH program, so you can get the command line on Palm. When I connect to my Mac OS X box with it (over TCP/IP mind you, though i think it can still do serial communication. Check out TopGunTelnet for pure-serial emulation.), tcsh by default has problems, most noticeably it seems to not to be able to run Pico or Vi (let alone Emacs).
I havn't messed around with it enough; i've only used it in cases where i need to a little command line hacking from my Treo.
--- Kicking the Cheat since late 2002
There are problems using PCs as dumb terminals. I remember a while ago at work we had a couple of Windows PCs hooked up to some Sun boxes, as dumb terminals. Of course the Windows PCs needed rebooting every now and then. Each time we rebooted them the Suns stopped.
We discovered that the PCs were sending a BREAK on the serial port, when they got rebooted. Once the came back up again, we'd find the Sun box sitting at the open firmware prompt:
ok>
Once we knew the problem, we could just unplug the PC before rebooting, but there were still lots of times someone forgot to do that.
It was VERY annoying
OK, so the article tells us how to enable logins from a serial port. That's great, but that's really only 1/2 the battle.
For various reasons (mainly driver development in a cramped office), I like to run serial CONSOLES. This means I want to see the kernel messages on the serial port, not on a VGA monitor. This allows me to log all kernel messages, even messages from a machine which crashed (hence syslog is not running). Otherwise, its easy for important messages to scroll off screen and be lost when the system crashes.
When running linux, getting a serial console is as simple as passing some parameters to the kernel (console=ttyS0). Similar options exist for FreeBSD, Tru64, Solaris, etc. All of them will use a serial port for a console.
With OS-X, I've been able to enable some extra verbosity on the serial port, and I'm able to get
an openfirmware prompt on the serial port, but I can't figure out how to make the serial port the actual system console. I know it must be possible, because the X serves are supposed to be able to do it.
Does anybody know how to do this on a "normal" g4 with a serial port (g4port)??
This might answer your questions (look at section 6):
http://www.netbsd.org/
Short answer:
setenv input-device ttya
setenv output-device ttya