Bug#686955: grub-installer: Grub fails to install on dm-crypt on LVM on SATA RAID 0
Package: grub-installer
Version: 1.78
Severity: important
Tags: d-i
Dear Maintainer,
I've been trying to install testing (wheezy) on a laptop with "SATA RAID" 0 (trying
to preserve dual boot with an existing Windows install). Used manual partitioning,
having booted installer with "dmraid=true" kernel flag. Set up a small partition
for /boot, and then a large dm-crypt partition, on which I created an LVM containing
"swap" and "root". Install failed when trying to install Grub (I think it tried to
install to hda1 or something like that). However, the Debian wiki on SATA RAID says
to expect failure, and fix this from rescue mode. So, reboot to rescue mode:
installer identifies the encrypted partition, mounts it and finds the encrypted
/dev/mapper/waif-root partition, so start a shell there. The wiki page says to run
"grub-install /dev/dm", which fails with a "no such disk" error; a comment suggested
using the base /dev/mapper name for the RAID array, which appears to be the right
thing: "grub-install /dev/mapper/isw_feefgadah_Volume0" doesn't complain about the
disk, but dies with "Autodetection of a filesystem of /dev/mapper/waif-root failed"
(waif is the name of my volume group).
Some online comments suggest that this is a problem with /boot/grub/device.map.
Here's mine:
(hd0) /dev/disk/by-id/usb-LG_USB_DRIVE_44C4435EF3D60051-0:0
(hd1) /dev/disk/by-id/ata-MZ-RPC512T_0SO_S0Z6NE0C601503
(hd2) /dev/disk/by-id/ata-MZ-RPC512T_0SO_S0Z6NE5C601503
(hd3) /dev/mapper/isw_feefgadah_Volume0
.... hd0 is the USB install disk; hd1 and hd2 the real hard drives; hd3 the RAID
array. This is exactly what grub-mkdevicemap produces. If I manually add this
line:
(hd4) /dev/mapper/dm-6_crypt
.... pointing to the encrypted volume containing the LVM, then the above grub-install
command executes without complaint. However, when I reboot it can't find its disc
and confronts me with a "grub> " prompt. I can get the install to work without
encryption, but this is undesirable for obvious reasons. Have you any suggestions
please?
-- System Information:
Debian Release: wheezy/sid
APT prefers testing
APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Kernel: Linux 3.2.0-3-amd64 (SMP w/8 CPU cores)
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
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