Make X Work on Diskless Linux

The following advice pertains to Fedora Core 6, and possibly other distributions, when the installation is modified such that the root filesystem is mounted read-only, and shared among a number of non-homogeneous systems. Date: Mon, 25 Jun 2007 15:46:53 -0400 From: Alex Aminoff Subject: How to make X possibly work on diskless linux ============================================= When a linux machine boots from our diskless root, most applications just automatically work with whatever hardware happens to be in the box. A major exception is X windows. Sometimes it will work with the default configuration, however sometimes auto-generating a machine-specific configuration will be necessary. 1. Try booting the linux machine diskless without any modifications to the default. Log in as a normal user and run startx. If the error messages obviously point to some other problem, like permissions on /tmp, try fixing those first. 2. The indications of a problem that generating a machine-specific xorg.conf is likely to fix are: X fails with error messages talking about drivers, or X starts up but fails to provide signal to the monitor, so that the monitor gets the "no signal" message. If the symptoms are something else, this procedure may work, but probably not. 3. Log in to the machine as root. 4. Create an in-memory file system for the /root directory. This is necessary because the place where the auto config generation deposits its output is hard-wired to /root/. On a diskless machine, /root is normally read-only. mount -t tmpfs none /root 5. Create the autogenerated xonfig Xorg -configure 6. Move the resulting file (/root/ to where it needs to go ( /disk/admin/conf/<machine>/etc/X11/xorg.conf ). This probably has to happen in 2 steps because you will not have write access to conf from the diskless machine directly. 7. Reboot the diskless machine and test.