Upgrading A Headless Server?

Paul Bristow writes "I've been using a Headless Linux server at home for years and years, but I always find myself putting off doing a distro upgrade. It always means digging out the old graphics card, keyboard and monitor, dusting them off and plugging them in, just so I can have a console to upgrade on. Are there any linux distributions that will allow remote upgrades? You know, log in as root viua ssh, webmin, whatever, run upgrade prog, remotely reboot, off we go. ;-) I know I'm not the only one running a headless server, and I *know* how stable it is, but occasionally RedHat (in my case) come out with a nice new feature that I might want to upgrade for. Also, with just one server it might just be possible, but how do you upgrade a headless server farm?"

Nik posted this relevant article back in March about the PC Weasel, which sounds like a good way to do this, at the cost of a small hardware investment per box. Are there better ones?

Comments

Try Debian

[compwizrd]

(insertyoureditorhere,soidon'tstartaflamewaraboute ditors) /etc/apt/sources.list, change to what version you want
apt-get update
apt-get upgrade

done.

you want debian :P

My modified Slackware can do this.

[Skapare]

I haven't actually done it headless (as in no video card), yet, but I have completely re-installed without using the keyboard, mouse, video, or any serial port. The way I did this was the way I layed out the system in the first place. Partition 1 has a 63meg self-contained rescue/maintenance system. The remainder of the drive is partitioned for the primary OS. Scripts included in the rescue/maintenance system can do the partitioning, reboot to see the new partitions, format the new partitions, and load the new OS file tree from over the network.

Unfortunately, this isn't helpful for your existing Redhat system. But it shows some ideas for things that can be done.

Easy enough under *BSD

[Echo|Fox]

You can do it exactly like you said in your example in FreeBSD (I'm sure Open and Net are the same). Just SSH in, su to root, CVSup source, make world, build an updated kernel, and reboot. The last time I upgraded one of my webservers I did it (sorta) this way even though that machine does have a little mono monitor. I'm not aware of any Linux distro's that you can upgrade like this, but any BSD users with headless servers may be interested...

Re:Reboot = no

[compwizrd]

set video to none, in your bios. most of the time, it'll run without a video card in it then.

You can use RPM to do a LIVE upgrade ...

[BitMan]

Have done this several times myself.

Just run rpm -Fhv *.rpm in your newer distro's RPM directory (e.g., /mnt/cdrom/RedHat/RPMS) and it will only upgrade those componenets that are install.

Heck, sometimes you don't even need to reboot! (although expect a few library issues until you do)

-- Bryan "TheBS" Smith

Re:Serial console?

[technos]

Redhat used to support serial terminals out-of-the-box. I know it still does on Sparc, because I just used it. Slap a nullmodem on the first serial port, set minicom for 9600 8N1. VT100 or ANSI, ANSI preferred. SuSe should support it as well. (Have seen it done, never actually done it however.)