# Help! Xorg "no devices detected" when booting from NFS, only

## sping

Hello!

I have a desktop machine with an ATI Radeon HD 3450 PCI Express graphics card. With my local setup 

x11-base/xorg-server 1.9.4

x11-drivers/xf86-video-ati 6.14.2

Kernel 2.6.36-gentoo-r8

Xorg detects the card out of the box. Great.

Now I also boot the same hardware into a system from the network using this Grub entry:

```
kernel (hd0,4)/boot/vmlinuz-2.6.36-gentoo-r8 root=/dev/nfs nfsroot=192.168.XX.XX:/XXX/ rw ip=dhcp raid=noautodetect
```

While the booting itself works well, Xorg does not detect my graphics card despite

identical versions of Xorg and the Radeon driver

identical version and configuration of the Kernel

Besides full auto-detection (i.e. empty /etc/X11/xorg.conf.d/) I have also tried manual pointing to the PCI Express slot (i.e. BusID "PCI:2:0:0"): still "no devices found".

Things I tried without luck:

Using other versions of the kernel

Using other versions of Xorg and the Radeon driver

Extracting working config using "Xorg -configure" from the local installation and feeding that to the NFS root troublemaker

Any idea why my results differ?

I am thankful for your help!

----------

## BradN

What happens if you chroot into the hard drive system after booting from NFS and then try to run X from the hard drive?  You will probably have to double mount or bind mount one or more of /dev, /proc, /sys into the hard drive filesystem.

Another thought, anything unusual in the xorg log file when running from NFS?

----------

## sping

 *Quote:*   

> Another thought, anything unusual in the xorg log file when running from NFS?

 

No.

 *BradN wrote:*   

> What happens if you chroot into the hard drive system after booting from NFS and then try to run X from the hard drive?  You will probably have to double mount or bind mount one or more of /dev, /proc, /sys into the hard drive filesystem.

 

Interesting idea. I tried that and X did not start from the disk-based chroot either.

I played with a catalyst stage4 now (rather than stage3 plus my own chroot scripts before). For some reason X detects my graphics card now. I noticed that udev was not added too sysinit level before. While I started testing with xdm initially most of my test were against "startx". Seems like it was udev not running.

Thanks for your help!

----------

## BradN

No problem  :Smile: 

Any idea how udev wasn't being started?  I thought it was always configured as default.

----------

## sping

 *BradN wrote:*   

> Any idea how udev wasn't being started?  I thought it was always configured as default.

 

I checked, it was not added to any runlevel. Also, it seems xdm does not depend on it. udev provides "dev" and no-one seems to depend on "dev". Wierd:

```
# fgrep -R "provide" /etc/init.d/udev

      provide dev

# fgrep -R "need" /etc/init.d/ | grep -w dev

/etc/init.d/udev:         need sysfs udev-mount udev-dev-tarball

/etc/init.d/udev-mount:   # Seed /dev with some things that we know we need

/etc/init.d/udev-dev-tarball:      need udev-mount
```

----------

