Boot from either RAID 1 drive in Centos 8
by furface from LinuxQuestions.org on (#5CV8T)
Hello, I installed a new Centos 8 distribution with 2 RAID1 mirrors. I want to be able to boot to either of the disks in case one fails. One boots, but not the other. Is there a way to enable this functionality? In previous distributions, either disk seemed to be able to boot. This is some info on my setup. Thanks.
[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md125 : active raid1 sdb2[1] sda3[0]
1047552 blocks super 1.2 [2/2] [UU]
bitmap: 0/1 pages [0KB], 65536KB chunk
md126 : active raid1 sdb1[1] sda2[0]
31246336 blocks super 1.2 [2/2] [UU]
md127 : active raid1 sdb3[1] sda4[0]
3874570240 blocks super 1.2 [2/2] [UU]
bitmap: 4/29 pages [16KB], 65536KB chunk
unused devices: <none>
[root@localhost ~]# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Wed Jan 13 19:41:53 2021
#
# Accessible filesystems, by reference, are maintained under '/dev/disk/'.
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info.
#
# After editing this file, run 'systemctl daemon-reload' to update systemd
# units generated from this file.
#
UUID=ef06be6d-d895-4da5-b597-c69cace09da4 / xfs defaults 0 0
[root@localhost ~]#
0 0
UUID=a3077ef9-f8c1-4807-acf9-86b501fb9490 none swap defaults 0 0
[root@localhost ~]# df
Filesystem 1K-blocks Used Available Use% Mounted on
devtmpfs 16309916 0 16309916 0% /dev
tmpfs 16329824 0 16329824 0% /dev/shm
tmpfs 16329824 9060 16320764 1% /run
tmpfs 16329824 0 16329824 0% /sys/fs/cgroup
/dev/md127 3872678360 28960048 3843718312 1% /
/dev/md125 1041288 202008 839280 20% /boot
tmpfs 3265964 0 3265964 0% /run/user/0
[root@localhost ~]#


[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md125 : active raid1 sdb2[1] sda3[0]
1047552 blocks super 1.2 [2/2] [UU]
bitmap: 0/1 pages [0KB], 65536KB chunk
md126 : active raid1 sdb1[1] sda2[0]
31246336 blocks super 1.2 [2/2] [UU]
md127 : active raid1 sdb3[1] sda4[0]
3874570240 blocks super 1.2 [2/2] [UU]
bitmap: 4/29 pages [16KB], 65536KB chunk
unused devices: <none>
[root@localhost ~]# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Wed Jan 13 19:41:53 2021
#
# Accessible filesystems, by reference, are maintained under '/dev/disk/'.
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info.
#
# After editing this file, run 'systemctl daemon-reload' to update systemd
# units generated from this file.
#
UUID=ef06be6d-d895-4da5-b597-c69cace09da4 / xfs defaults 0 0
[root@localhost ~]#
0 0
UUID=a3077ef9-f8c1-4807-acf9-86b501fb9490 none swap defaults 0 0
[root@localhost ~]# df
Filesystem 1K-blocks Used Available Use% Mounted on
devtmpfs 16309916 0 16309916 0% /dev
tmpfs 16329824 0 16329824 0% /dev/shm
tmpfs 16329824 9060 16320764 1% /run
tmpfs 16329824 0 16329824 0% /sys/fs/cgroup
/dev/md127 3872678360 28960048 3843718312 1% /
/dev/md125 1041288 202008 839280 20% /boot
tmpfs 3265964 0 3265964 0% /run/user/0
[root@localhost ~]#