[Mageia-dev] GRUB can't see HD from chroot unless parent /dev is bind-mounted in chroot ?

Wed Jan 16 17:24:50 CET 2013

'Twas brillig, and Frank Griffin at 16/01/13 16:03 did gyre and gimble:
+> I've been re-running /boot/grub/install.sh from within chroots for years
+> with no problem.  But today when I tried doing this, I consistently got
+> Error 21: no such device.  After googling a bit, I noticed that if I
+> started grub in the rescue system and did "grub> geometry (hd0)", I got
+> a correct response, but when I did the same thing from a chroot, it got
+> Error 21.
+> 
+> If I bind-mount the rescue system's /dev to the chroot's /dev, it works
+> fine.
+> 
+> This makes perfect sense, except for the fact that I've never had to do
+> it before.  Any idea what changed ?  This has the potential to screw up
+> a lot of folks who were used to the old way.
+> 
+> Maybe /dev/sdX entries are no longer static, and so don't exist on the
+> root partition unless it is the booted system ?
+
+It's quite possible that the lack of static nodes is what's messing
+things up.
+
+Personally I've been bind mounting /dev, /proc and /sys for years
+whenever doing any rescuecd etc. stuff. Partly because I have several
+LVM volumes where a static /dev/ wouldn't help anyway...
+
+But bind mounting /dev has just been part of my chroot routine for as
+long as I remember.
+
+Col
+
+
+-- 
+
+Colin Guthrie
+colin(at)mageia.org
+http://colin.guthr.ie/
+
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