Root Drive Mirroring and LVM.

[Dean Takemori]

I don't know if the raid bits actually work or not, but building a 
2.4.24
kernel with CONFIG_MD and CONFIG_MD_RAID* set to y results in a
working kernel.

In addition, setting CONFIG_BLK_DEV_LVM to y also results in a
working kernel.

However, there's something not quite working with LVM.  With a 2.4.24
kernel built as above on my Wallstreet powerbook, and following the 
linux
HOWTO at <http://tldp.org/HOWTO/LVM-HOWTO/>, I've attempted to
create an LVM setup on an external SCSI disk (I'm booting off the 
internal
drive).

Most of the commands (pvcreate, lvcreate etc.) appear to work at first,
except for vgscan, which dumps core.

~ > sudo vgscan -v
vgscan -- removing "/etc/lvmtab" and "/etc/lvmtab.d"
vgscan -- creating empty "/etc/lvmtab" and "/etc/lvmtab.d"
vgscan -- reading all physical volumes (this may take a while...)
vgscan -- scanning for all active volume group(s) first
vgscan -- found active volume group "vg"
vgscan -- reading data of volume group "vg" from physical volume(s)
Segmentation fault (core dumped)

  Ignoring that, I was able to create several logical volumes, initialize
them, put an ext2 filesystem on them and then mount them.

~ > df -h /dev/vg/*
Filesystem            Size  Used Avail Use% Mounted on
/dev/vg/group         496M  101M  369M  22%
/dev/vg/home         1008M   20K  956M   1% /mnt/Temp/home
/dev/vg/root         1008M  872K  955M   1% /mnt/Temp
/dev/vg/usr          1008M   20K  956M   1% /mnt/Temp/usr
/dev/vg/var          1008M   20K  956M   1% /mnt/Temp/var

Unfortunately, something about the lvscan crash isn't working.

~ > sudo lvdisplay -v /dev/vg
lvdisplay -- ERROR: VGDA in kernel and lvmtab are NOT consistent; 
please run vgscan

Since this isn['t working, I haven't actually tried to use the mounted
volumes for anything.

I wonder, do I have to recompile the lvm tools for my kernel?

Any help is appreciated.

Note: There was a recent discussion of LVM on Linux/PPC recently
on the debian-powerpc list, with the upshot being that someone there
may have gotten it working.


 >From: "Donald L. Gover" <dlgover1@earthlink.net>
 >
 >Does anyone have any experance or info on whether the raid and lvm
 >packages have been ported to YDL? I'd like to set up a raid 1 mirror 
of my
 >root drive to allow for a alternate boot should one drive fail. Then 
also
 >provide for raid 1 mirros of some user data while using Logical Volume
 >manager to carve up  a large section of disk. Can anyone comment if 
this
 >is possible with YDL?
 >
 >  Donald L. Gover