/boot/efi partitions on software RAID1

[kenn]

Hello! I have a problem on installing CentOS 6.5 in Software RAID1 system.
I want to set up software RAID1 on two SATA HDD.
When I have installed CentOS, I have warned from installer
"You have not created a /boot/efi partition."
nevertheless I have created a /boot/efi partition in a /dev/md0 (RAID1 drive).

What I wonder is when I create a /boot/efi partition as a normal partition(non RAID)
"EFI System Partition" can be selected as a format type.
On the other hand, for md0(RAID1), the "EFI System Partition" item is disappeared
and cannot be selected.
(So I chose other formats, vfat and ext4.)
(nether of them working.)

In my understand, boot partition can be placed on RAID1 drive.

How can I install /boot/efi on RAID1 drive?
Please guide me.
Thank you.

[Super Jamie]

I have created a /boot/efi partition in a /dev/md0 (RAID1 drive)

You can't do this. The EFI specification mandates that the firmware recognise a FAT32 partition as the EFI System Partition. The firmware cannot recognise Linux Software RAID as an EFI System Partition.

The correct way is to install your /boot and / and other filesystems on software RAID, and to duplicate the FAT32 partition in sda1 onto sdb1, then create another EFI firmware boot menu entry pointing to the backup partition.

[kenn]

Thank you for your quick response.

I have tried what you said, but still have a trouble.

/boot and / and other filesystems on software RAID

I made two RAID drives, md0 for /boot, md1 for /
Then installer still warn
"You have not created a /boot/efi partition."

Should I have to make a partition /boot/efi separately?
And if so, on which drive(sda or sdb) should I make a partition?

[Super Jamie]

Should I have to make a partition /boot/efi separately?
And if so, on which drive(sda or sdb) should I make a partition?

Yes, that's right, you need to have something like:

sda (first drive)
- sda1 - FAT32 - /boot/efi - in firmware boot menu as "CentOS"
- sda2 - Linux software RAID - /boot
- sda3 - Linux software RAID - /

sdb (second drive)
- sdb1 - FAT32 - copy of /boot/efi - in firmware boot menu as "CentOS Backup"
- sdb2 - Linux software RAID - /boot
- sdb3 - Linux software RAID - /

[kenn]

Thank you for your quick response again!
I am not well versed in Linux so much,
So please teach me some points.

- sda1 - FAT32 - /boot/efi - in firmware boot menu as "CentOS"

I think it's OK.

But,I cannot understand the next.

- sdb1 - FAT32 - copy of /boot/efi - in firmware boot menu as "CentOS Backup"

How can I "copy" the /boot/efi?
How can I "menu" the "CentOS Backup"?

It may be a dull questions,
please forgive my ignorance.
Thank you.

[Super Jamie]

For the first, you can use dd or cp commands.

For the second, use efibootmgr command.

[kenn]

Thank you for your kindness.
I will try it later.

[kenn]

Hello.
I tried Jamie's advice just now.
(Please forgive me for the time lag.)
But I cannot have a conviction about what I have done.
Would you confirm my procedure?

Code: Select all

# dd if=/dev/sda1 of=/dev/sdb1
# efibootmgr --create --disk /dev/sdb --label "CentOS Backup" --load "\\EFI\\redhat\\grub.efi"         

After this, on UEFI BIOS boot menu, "CentOS Backup" menu is appeared, and I can boot from this menu.

Is this the correct procedure?
And is this all to do for me?

[Super Jamie]

That's it as far as I know.

[kenn]

Thank you!