How to make Grub boot from primary as well as secondary disk of RAID1 Array

I am currently installing SuSE Linux 15. I wish to secure this system against Disk failure hence opted to configure software RAID 1 on disk1 (sda) and disk2 (sdb). Basically during installation configured the disks partitions in RAID 1 and then created following partitions. /boot/efi md0 (sda2+sdb2) /boot md1 (sda3+sdb3) /swap md2 (sda4+sdb4) / md3 (sda5+sdb5) I then tested this system, by removing sdb system, and the system could boot without problem. But when I removed the disk sda(primary) disk, the system could not go part Grub. After analysing, I have realised the Grub is configured in such a way that it points to software raid parition md1 but it must have both the disks present, ie working software raid, in order to be able to boot the system using that device md1. I am not okay with this if this is really true. The basic idea of having software raid for /boot device is that in case of hardware failure, the system should use the other working disk and boot. Isn't it the software raid 1 meant for? I am really confused now. If you require any more system details please ask. But how do i secure the system (boot) against hardware failure. The disks do eventually fail. So there must be some solution. It just that I do not know it yet. Regards. Here is the output of the commands you asked for, localhost:~ # lsblk -f | grep -v loop | sed -E 's/\w{8}-\w{4}-\w{4}-\w{4}-\w{12}/XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX/' NAME FSTYPE FSVER LABEL UUID FSAVAIL FSUSE% MOUNTPOINTS sda ├─sda1 ├─sda2 linux_raid_member 1.0 any:0 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX ├─sda3 linux_raid_member 1.0 any:1 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX ├─sda4 linux_raid_member 1.0 any:2 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX │ └─md2 swap 1 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX [SWAP] └─sda5 linux_raid_member 1.0 any:3 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX sdb ├─sdb1 ├─sdb2 linux_raid_member 1.0 any:0 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX │ └─md0 vfat FAT32 ADB7-4EE5 1021.9M 0% /boot/efi ├─sdb3 linux_raid_member 1.0 any:1 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX │ └─md1 ext4 1.0 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX 853.8M 7% /boot ├─sdb4 linux_raid_member 1.0 any:2 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX │ └─md2 swap 1 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX [SWAP] └─sdb5 linux_raid_member 1.0 any:3 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX └─md3 ext4 1.0 XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX 4.4G 54% / sr0 iso9660 Joliet Extension SLE-15-SP6-Full-x86_6493.51.001 2024-06-13-19-56-33-00 localhost:~ # fdisk -l Disk /dev/sda: 15 GiB, 16106127360 bytes, 31457280 sectors Disk model: VBOX HARDDISK Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 0E77630A-CBC9-4C1F-9321-D7886DAC09BC Device Start End Sectors Size Type /dev/sda1 2048 104447 102400 50M BIOS boot /dev/sda2 104448 2201599 2097152 1G Linux RAID /dev/sda3 2201600 4298751 2097152 1G Linux RAID /dev/sda4 4298752 8493055 4194304 2G Linux RAID /dev/sda5 8493056 31457246 22964191 11G Linux RAID Disk /dev/sdb: 15 GiB, 16106127360 bytes, 31457280 sectors Disk model: VBOX HARDDISK Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 07F46E03-A25D-4305-BCFD-E79ADEA113C1 Device Start End Sectors Size Type /dev/sdb1 2048 104447 102400 50M BIOS boot /dev/sdb2 104448 2201599 2097152 1G Linux RAID /dev/sdb3 2201600 4298751 2097152 1G Linux RAID /dev/sdb4 4298752 8493055 4194304 2G Linux RAID /dev/sdb5 8493056 31457246 22964191 11G Linux RAID Disk /dev/md1: 1023.94 MiB, 1073676288 bytes, 2097024 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk /dev/md3: 10.95 GiB, 11757551616 bytes, 22963968 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk /dev/md0: 1023.94 MiB, 1073676288 bytes, 2097024 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00000000 Disk /dev/md2: 2 GiB, 2147418112 bytes, 4194176 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Respective Partitions: /dev/sda1 --> BIOS BOOT Partition /dev/sda2 --> BIOS BOOT Partition /dev/md0 (sda2+sdb2) : /boot/efi /dev/md1 (sda3+sdb3): /boot /dev/md2 (sda4+sdb4): /swap /dev/md3 (sda5+sdb5): /