new Install advice sought

I want to setup a “Server” PC with 2 x 4Tb Hard Drives

I would like this to be SOFTWARE RAID1

are there any recomendations how to achieve this ?

I have setup Software RAID with SLES11 in the past
looks like things have changed a bit

I have tried using this https://documentation.suse.com/sles/15-SP1/html/SLES-all/cha-raid.html

Whilst I can mirror / the problem I’m having is BOOTING
after forced failure of 1st disk

Any How to’s or pointers would be appreciated

Also, ideas on how to partion the 4TB
I like to keep the OS parations small

Boot method? EFI or legacy???
Soft RAID does not kick in until the kernel loads so how is the BIOS to know which drive to boot from unless you use fake RAID??
If EFI have you provides a efiboot partition on the second drive? This should be set to boot the second drive and and be second in boot order in UEFI boot table.

EFI I’m guessing

Can the EFI partition be Raided ?

Bit confused iwth EFI

or do I create EFI partion on both drives

Then once installed dd copy the EFI from 1st disk
then use boot Yast Boot loader to install Boot on 2nd disk ?

Don’t think you can just make a copy it must be registered in the UEFI for one thing. Also would need to be the secondary boot entry in the UEFI boot table.

If you don’t know how it boots (really??) show **fdisk -**l that will show if you have an EFI boot partition or not on each drive. A;sp in yast boot loader you would use grub for EFI as the boot loader

I don’t use RAID myself just know boot procedures. So not sure how to set this up. My guess is the instructions you used assumes legacy/MBR booting since without the A drive in the array there would need to be full boot code on B drive if EFI.