Bypass CD media search?

Post in this forum for problems at boot time, if there was no problem for burning the disc. For example can't find the CD, or strange errors when you press enter at the very first prompt.
Post Reply
Tarquin
Posts: 2
Joined: 16 Aug 2007, 03:05

Bypass CD media search?

Post by Tarquin » 16 Aug 2007, 03:52

I'm trying to use SysRescueCD 0.3.7 to recover data from a machine with a failing hard disk. (It also has a second, working, disk - the plan is to fire up the CD and use ddrescue to clone as much of the disk as I can, so I can search that with recovery tools and send the dead disk off for replacement).

The CD boots fine, recognises all my hardware - no problems there. Unfortunately, it insists on scanning all the disks it can see to find the CD, and when it tries this on the faulty hard disk (sda, so earlier in the search order than hda, which is the CD drive), it hangs. I've left it for up to twenty minutes hoping for it to time out, but nothing happened, and the system wasn't responding to keyboard input either.

Is there any way I can just tell the system "Your CD is on this device, don't bother scanning the others"? Failing that, some way of not loading the SATA drivers at bootup would work too. I've tried nodetect, ide=nodma, cdroot=/dev/hda, root=/dev/hda, and noload= in various combinations, none of which seem to have any effect. (Neither noload=sata_nv nor noload=sata_nv,sd,scsi prevent the SATA drivers from being loaded; are they compiled into the kernel, or what?)

Any suggestions would be gratefully received; thanks in advance.

admin
Site Admin
Posts: 2715
Joined: 17 Jul 2003, 09:44

Post by admin » 16 Aug 2007, 20:29

- you cannot use noload=xxx there because these drivers are built-in
- if the driver hangs, it probably means you have an hardware failure

Tarquin
Posts: 2
Joined: 16 Aug 2007, 03:05

Post by Tarquin » 17 Aug 2007, 05:46

Well, yes, I know I have a hardware failure - that's the reason I'm using SysRescueCD in the first place. (I know the damaged disk isn't completely dead, so I want to recover what data I can to a working disk.) I'd like to be able to tell the system "no, don't probe that disk, it's broken - your CD is over here".

Being able to specify the location of the CD and bypass the automatic search would be the best way to do this, since you could easily have a case where just disabling the driver wouldn't help (for instance, faulty disk on hda, booting from a CD drive on hdb); it shouldn't really be necessary for the user to open up their machine and rearrange device connections to get the system to boot.

However, it looks like the only way to get around the problem in my case would be to rebuild the kernel and initrd on the CD, with sata_nv built as a module, so that I could use the noload= boot parameter. If so, that seems like quite a lot of work; it's probably easier to just see if I can find a halfway error-tolerant disk cloner for Windows instead.

Post Reply