[Mageia-dev] Issues with dracut

Sun Dec 18 04:00:51 CET 2011

'Twas brillig, and David W. Hodgins at 18/12/11 00:04 did gyre and gimble:
+> On Sat, 17 Dec 2011 15:21:14 -0500, Colin Guthrie
+> <mageia at colin.guthr.ie> wrote:
+> 
+>> Dracut should install all dynamic libs needed by apps. Which app needs
+>> this library specifically?
+> 
+> When I tried to boot after running dracut with the default config, I
+> was dropped to a shell, with the non-lvm root mounted.
+> 
+> I then tried running "/sbin/lvm vgchange -a y --ignorelockingfailure",
+> and it failed due to the missing libncursesw.so.5 module.
+> 
+> Now that I think about it, a bit more, I think I had already been
+> chrooted into the root, so since /usr hadn't been mounted, of course
+> the module could not be accessed.  Something else must have gone wrong
+> before the chroot, that I didn't see.
+
+Ahhh interesting. Could have been a filesystem check error. What
+filesystem do you have on your /usr ? (obviously on top of the lvm layer).
+
+Did typing "mount /usr" just work? After that (and typing exit) does
+everything work as expected?
+
+> Do you have /usr on a logical volume?
+
+In my test VM yes, I had / on ext4 and /usr on LVM also with ext4.
+
+> I've figured out now, that /lib/dracut/hooks/pre-pivot/50mount-usr.sh is
+> failing, as lvm has not yet been activated.
+
+That's strange, as lvm should be activated by then. Was the lvm module
+included in your ramfs? The latest version should detect LVM on the /usr
+partition, but it's perhaps not full proof (I only tested it in my test
+vm when I wrote it).
+
+> Later, I'm dropped to a shell, after the switch to the new root, and
+> since /usr hasn't been mounted, any commands that try to load
+> /usr/lib/libncursesw.so.5 such as lvm, grep, or less, will fail.
+> 
+> When I've copied /usr/lib/libncursesw.so.5* to /lib and run ldconfig,
+> it still fails in 50mount-usr, but succeeds later, after the root
+> switch.
+> 
+> The dm-mod module loading, and the "lvm vgchange -ay --sysinit" command
+> should be run before looking for the root file system, as it too could be
+> on a logical volume.
+
+They all should be (and are for me). I suspect the missing link is that
+the lvm module is not being included in your ramfs... If we can work out
+why it would be great.
+
+The shell script you'll need to tweak is
+/usr/lib/dracut/modules.d/90lvm/module-setup.sh.
+
+The code is fairly easy to follow and you can probably hack out the bits
+to make it a simple runable script to see if you can work out why lvm is
+not being included.
+
+Col
+
+-- 
+
+Colin Guthrie
+colin(at)mageia.org
+http://colin.guthr.ie/
+
+Day Job:
+  Tribalogic Limited http://www.tribalogic.net/
+Open Source:
+  Mageia Contributor http://www.mageia.org/
+  PulseAudio Hacker http://www.pulseaudio.org/
+  Trac Hacker http://trac.edgewall.org/
+