Running Old Desktops Headless?

CajunArson writes "I recently dug up an old P4 that is in fine working order and did what any self-respecting Slashdotter would do: I slapped Linux on it to experiment with making an NFSv4 server. One other thing I did was to remove the old AGP video card to save on power, since this is a headless machine. Now, I removed the video card after the installation, and I'm doing just fine as long as the machine will boot to a state where networking works and I can SSH to it. My question: Is there a good solution to allow me to log into this box if it cannot get on the network? I'm looking for solutions other than slapping a video card back in. In my case, I will have physical access to the machine. A few caveats to make it interesting: This question is for plain old desktop/laptop systems, not network servers designed to run headless. Also, I am aware of the serial console, but even 'old' machines may only have USB, and I have not seen any good documentation on how and whether USB works as a substitute. Finally, if there is any way to access the BIOS settings without needing a video card, that would be an extra bonus, but I'm satisfied with just local OS access starting from the GRUB prompt."

Comments

Re:Serial console

[value_added]

A serial console. As far as I know, this is what serial ports were actually put into computers for in the first place.

Sigh. I wish more people (the home user Slashdot types) would just go buy a serial cable (and/or serial+USB adapter) and see for themselves how trivial it is to set up, and how valuable that setup can be. There's plenty of reasons why one would *want* to rely on serial, aside from the usual "What if the network is down?" scenario.

For added fun (when there's more than one computer involved), consider something like this

The question about bios settings is a good one though, and I don't know.

For the OP and most of us, that's a noop. What I would have suggested instead of a powerhungry P4 (or even PIII), is a soekris box. There's no VGA at all, so the BIOS (and everything else) is accessible via serial only. My "headless" VIA boxes are a PIA by comparison.

Granted, Soekris boxes are typically used to perform networking functions, but setting one up with a hard drive (laptop or SSD ideally) and running a web, IMAP, NFS, Samba, etc. server is common enough and performance is perfectly adequate. A few bucks more, but hey, they're rackmountable so you can impress your friends and neighbours. :-)

Re:Good luck

[Anonymous Coward]

Grub works just fine with serial console. Add the following lines to your grub.conf:

    serial --unit=0 --speed=38400 --word=8 --parity=no --stop=1
    terminal --timeout=10 serial console

Also, make sure to add:

    console=tty1 console=ttyS0,38400n8

to your "kernel" line for linux boot images so the kernel will send console messages to the console. Of course the kernel itself must be configured to support serial console too!

RTFLDP

[itomato]

From the Remote Serial Console HOWTO http://tldp.org/HOWTO/Remote-Serial-Console-HOWTO/configure-boot-loader-grub.html
GRUB:

Define the serial port and configure GRUB to use the serial port, as shown in Figure 4-6. Figure 4-6. GRUB configuration for serial console

serial --unit=0 --speed=9600 --word=8 --parity=no --stop=1
terminal serial

--unit is the number of the serial port, counting from zero, unit 0 being COM1. Note that the values of --parity are spelt out in full: no, even and odd. The common abbreviations n, e and o are not accepted. If there is mysteriously no output on the serial port then suspect a syntax error in the serial or terminal commands. If you also want to use and attached monitor and keyboard as well as the serial port to control the GRUB boot loader then use the alternative configuration in Figure 4-7.

Kernel:

The Linux kernel is configured to select the console by passing it the console parameter. The console parameter can be given repeatedly, but the parameter can only be given once for each console technology. So console=tty0 console=lp0 console=ttyS0 is acceptable but console=ttyS0 console=ttyS1 will not work. When multiple consoles are listed output is sent to all consoles and input is taken from the last listed console. The last console is the one Linux uses as the /dev/console device. The syntax of the console parameter is given in Figure 5-1. Figure 5-1. Kernel console syntax, in EBNF

console=ttyS<serial_port>[,<mode>]
console=tty<virtual_terminal>
console=lp<parallel_port>
console=ttyUSB[<usb_port>[,<mode>]

Quite a bit more info at tdlp.org..

Re:Good luck

[hairyfeet]

Actually there is an even cheaper and easier way to do it.....go talk to your friendly neighborhood local mom and pop repair shop. We are the biggest packrats there is and often have drawers filled with old PCI cards of all shapes and sizes. We are also usually quite bored and will happily sell you parts cheap, especially if you are doing something cool with them like a server, instead of dealing with the usual "I got a bug looking at pron again. Here fix it" which is what our days usually consist of. I personally have everything from a 2Mb Matrox card up to a 64Mb MX400 lying in my GPU drawer.

So go talk to your local repair shop. you'll find if you BS with us a little we're happy to let you go through the goodie drawers and will sell you cheap anything you want. Think of it like a cheap flea market for PC parts. We just really hate throwing working hardware away when we might find a use for it someday. And before somebody goes "WTF you gonna do with those old crappy GPUs?" I would point not only to this article, but point out the fact I just sold a 12Mb S3 graphics card to a guy for a whole $5 including popping it in for him. It was supposed to be just to get him through until we could get him an AGP card (which I was out of at the time) but the S3 worked great on his Win2K office PC so he said "if it ain't broke, why fix it?".

Those old PCI cards with 8-16Mb of RAM really didn't use hardly any juice at all, probably less than the average IGP does today. 20 minutes worth of BSing with your local repair guy and I'm sure you'll get one for a couple of bucks, with no shipping or waiting. Then if you want to get fancy you can pick up one of the cheapo KVM switches at Newegg, and if you have a problem with your server just "clicky clicky" on the keyboard shortcut and you are good to go. I paid a whole $30 for mine but Newegg has the same model for $26 or $16 for a 2 port. Since you already have the P4 this would be the easiest way to go headless and still have access if something goes wrong.