Partitioning EFI machine with two SSD disks in mirror

Question

I have two SSD disks, I want to put them in a software mirror RAID.

But whatever I do the OpenSuSe installation keeps telling me that due to the partitioning scheme he won't be able to install the bootloader.

How should I partition the disks? Also what block sizes should I use for the raid?

I tried the following:

ssd1 -> FAT EFI (256MB)
     -> Raid 1/2 mirror swap (4GB)
     -> Raid 1/2 mirror LVM (~50GB)

ssd2 -> empty (256MB)
     -> Raid 2/2 mirror swap (4GB)
     -> Raid 2/2 mirror LVM (~50GB)

LVM  -> root (25GB)
     -> home (~25GB)

Solution 1

So apparently there are several issues and several approaches to handle this.

EFI should be able to handle RAID paritions, but only with metadata <= 1.0

Newer version of metadata are stored on the beginning of the partition (screwing up the filesystem detection).

You can go without extra /boot partition if you integrate the /boot into /boot/efi after the installation.

What I ended up doing was this (two disks, RAID 1):

• create a layout where you have a non-raid, non-lvm /boot/efi
• create an empty counterpart on the other disk (same size)
• create a /boot that is non-lvm (can be raid)
• create the othe partitions (root, home, swap, etc...)
• let the install do it's work
• clone the /boot/efi using dd
  • dd if=/dev/sda1 of=/dev/sdb1
• add an efi record for the clone
  • efibootmgr -c -g -d /dev/sdb -p 1 -L "opensuse" -l '\EFI\opensuse\grubx64.efi'
• using efibootmgr --bootorder change the boot order so that the two opensuse (or whatever your distro is) records are next to each other

Solution 2

I am not that familiar with SUSE but i think that the boot partition always has to be outside lvm.

the kernel loads the lvm module and then can access the lvm-disks but not before. so you need a 500MB /boot partition outside lvm that can hold the kernel image.

As far as i read you need a special bootmanager to be able to boot form EFI:

I am not sure if this is helpful for you, i only found some german ressources regarding efibootmgr and the corresponding manpage man efibootmgr.

.I always avoided EFI so far and changed to normal bios

Comments

[Šimon Tóth]

I actually tried that as well. The thing is that the EFI is the boot partition, you can't even select /boot during the install with EFI turned on. When I done this manually I ended up with an unbootable system.