Hi list! I've just completed migrating my system from one hard disk to another. Although the new disk reports 512 byte blocks just like the old one, I thought it would be a good idea to re-align the partitions anyway. I've done it this way:
1. Create new partitions with gparted, at least as large as the old ones
(rounded up to full MiB).
2. `dd` from the old to the new disk.
3. `resize2fs` to match the new sizes.
4. Install grub ("root (hd1,4); setup (hd1); setup (hd1,4)")
4. Swap disks and reboot.
Unfortunately, the system failed to find the boot loader. There was no
grub error. The disk was simply skipped, as if it was unformatted.
The following steps were taken:
1. Verified that the `dd`ed partitions were sane.
2. Reinstalled grub from live-CD chroots several times.
3. Installed grub on a memory stick and booted from that.
At this point, my partition table looked like this:
Number Start End Size Type File system Flags
1 1049kB 316MB 315MB primary ntfs
2 316MB 750GB 750GB extended
5 317MB 424MB 107MB logical ext2 boot
6 425MB 22.4GB 22.0GB logical ext3
7 22.4GB 28.9GB 6441MB logical linux-swap(v1)
8 28.9GB 750GB 721GB logical
The first logical partition was the boot partition. The first primary
partition was a laptop-specific recovery partition. This setup was
identical to the old one except that I removed a primary partition which
resided /after/ the end of the extended partition.
At this point, I've reformatted the first primary partition as ext2 and
moved boot to this partition. This solved my problem.
Now, my question is: Why does this work and the old solution doesn't?
Why can't grub boot from a logical partition when it's MiB-aligned? I've
changed nothing that should affect the MBR. Then why wasn't at least the
stage 1 detected?
Thanks in advance!
Florian Philipp
signature.asc
Description: OpenPGP digital signature
