Initrd problems/lvm (was: Re: How-to for dmraid OS drive(s)?)

Fri Aug 26 12:14:57 UTC 2005

Hello -

I went through the steps recommended (included at the bottom here) and 
got as far as rebooting my system after making a fresh initrd with the 
patch provided to mkinitrd and I get a kernel panic that seems to be a 
common problem for people installing Fedora core 4.  If I switch the 
BIOS back to booting from my auxilliary drive, everything works fine.

I don't have the exact error message in front of me (unfortunately), but 
it's almost identical to this where it can't find a vg and lvm throws 
error 5 (and the /dev/console complaint):
-----------------------------------------------------------
Red Hat nash version 4.2.15 starting
  Reading all physical volumes.  This may take a while...
  No volume groups found
  Unable to find volume group "VolGroup00"
ERROR: /bin/lvm exited abnormally with value 5 ! (pid 454)
mount: error 6 mounting ext3
ERROR opening /dev/console!!!!: 2
error dup2'ing fd of 0 to 0
error dup2'ing fd of 0 to 1
error dup2'ing fd of 0 to 2
switchroot: mount failed: 22
Kernel panic - not syncing: Attempted to kill init!
------------------------------------------------------------

Except in my case, it finds "VolGroup00", which is my old "/" filesystem 
on an lv on the old drives, and does not find my new vg on the SATA mirror.

Couple questions here.  I've changed fstab and grub.conf -- I've 
disabled the other drives in Bios and/or unplugged them -- is it vgscan 
that is picking them up or is there a stale pointer somewhere I may have 
copied over in my:

|find / -xdev -print0 | cpio -pa0V --sparse /mnt/temp

And is _everything_ in /dev dynamic or does there need to be something 
in there on the new drives?

The way I have fstab and the partitions setup is I have:
/dev/mapper/sil_<something>1 as /boot
/dev/mapper/sil_<something>2 as swap
/dev/myvg/mylv which contains the PV /dev/mapper/sil_<something>3 which is /

I did _not_ change the labels on the old LV/static partitions and 
perhaps that is causing issues (because they are the same)?

In a small stab in the dark, I also tweaked mkinitrd so the raid stuff 
came before the lvm stuff (since my lv is on the sil 3114 mirror) and I 
was sure to run mkinitrd against the new fstab in /mnt that I had 
changed appropriately.

Any ideas?

Thanks,

Steve
|
Lin, Weichuan wrote:

>On my SIL 3114 chip, I have successfully migrated a system to raid, here
>is the operation step:
>
>Steps to port an existed system to SATA RAID:
>
>   1. Prepare an auxiliary hard disk with a system installed, for
>example, EL4.
>   2. Make Stripe (RAID 0) with the help of utility of Silicon Image at
>the stage right after Power on self test and before the start of grub.
>   3. Boot up the EL4 host on the auxiliary hard disk.
>   4. Active the RAID with the help of dmraid, and the new device called
>/dev/dm-0 can be seen.
>   5. Use fdisk or parted to slice hard disk partitions on device of
>/dev/dm-0. Typically one for /boot, the other on for swap, and the last
>one for /, don't forget to active boot flag of the partition for /boot.
>After doing that, device called /dev/dm-1, /dev/dm-2 and /dev/dm-3 can
>be seen, also device mapper under /dev/mapper appears. For controller of
>SIL 3114 CTU, there are sil_afageidcdibjb and sil_afageidcdibjb1 etc.
>   6. Make file system on /dev/dm-1 and /dev/dm-3 with the utility of
>mkfs.
>   7. Mount /dev/dm-1 foo and mount /dev/dm-3 bar.
>   8. Copy all files under /boot to foo and files under / to bar, with
>cp -au, like cp -au /boot foo. For the copying of /, the top level
>directories need to be copied separately to exclude the mount point of
>/dev/dm-1 and mount point of /dev/dm-3.
>   9. manually install GRUB to the device of dm-0, like: 
>
>9.1      Call grub --device=/dev/null to enter grub shell.
>
>9.2      Grub>device /dev/mapper/sil_afageidcdibjb (hd0) [Caution: can't
>use /dev/dm-0 here]
>
>9.3      Grub>geometry (hd0) [check if the right device is mapped to
>(hd0), if it is right, you can see that there are three partitions]
>
>9.4      Grub>root (hd0,0) [successfully execution, grub can recognize
>the file system on /dev/dm-1]
>
>9.5      Grub>setup (hd0) [install the grub to /dev/dm-0, ie.
>/dev/mapper/sil_afageidcdibjb , every stage should be successful]
>
>9.6      Grub>quit
>
> 
>
>Note: before install the grub, the grub.conf may be kept as simple as
>possible. It is better to comment some options like splashimage and
>hiddenmenu to ensure the successfully display of the grub menu after
>reboot.
>
> 
>
>  10. Copy the dmraid.static to /sbin. This utility is the static link
>version of dmraid and is needed at intird stage. It is not included in
>the distribution of EL4, but it can be found at the distribution of
>Fedora4, just copy it.
>  11. Path the mkinird, see the end.
>  12. make initrd with mkinitrd, like mkinitrd initrd.new `uname -r`
>  13. copy the initrd.new to foo.
>  14. edit the foo/grub/grub.conf to provide entry of current kernel and
>the new initrd.img. Like: 
>
> 
>
>title SATA RAID
>
>root (hd0,0)
>
>kernel /vmlinuz-2.6.9-5......     root=/dev/dm-3  ....
>
>initrd  /initrd.new
>
> 
>
>15. Edit the bar/ect/fstab to change the device of root file system,
>like: 
> 
>
>            /dev/dm-3          /           ext3      defaults 1  1
>
>            /dev/dm-1          /boot     ext2      defaults  1  2
>
>            /dev/dm-2          swap     swap     defaults  0  0
>
>....................................
>
> 
>
>  16. halt -p to stop the current system.
>  17. Detach the auxiliary hard disk. And re-power on the machine. Enjoy
>it!
>
>patch for /sbin/mkinitrd
>
>--- mkinitrd    2004-10-25 06:01:52.000000000 +0800
>+++ mkinitrd.new    2005-07-01 07:12:33.000000000 +0800
>@@ -733,6 +733,18 @@ elif [ -n "$root_lvm" ]; then
>   fi
> fi
> 
>+#add to active dmraid
>+if [ -x /sbin/dmraid.static -a -x /sbin/dmsetup -a -e
>/dev/mapper/control ]; then
>+ dmout=$(/sbin/dmsetup ls  2>/dev/null)
>+ if [ "$dmout" != "No devices found" -a "$dmout" != "" ]; then
>+    inst /sbin/dmraid.static $MNTIMAGE/sbin/dmraid
>+          echo "echo Making device-mapper control node" >> $RCFILE
>+    echo "mkdmnod" >>$RCFILE
>+    echo "echo Running dmraid to active reid" >>$RCFILE
>+    echo "/sbin/dmraid -ay" >>$RCFILE
>+ fi
>+fi
>+
> echo "echo Creating root device" >> $RCFILE
> echo "mkrootdev /dev/root" >> $RCFILE
> rootdev=/dev/root
>  
>