[CentOS] Looking for a RAID1 box

Thu Jan 12 14:48:01 UTC 2023
Fleur <afsupertek at gmail.com>

Hi All, very interesting thread, I add my 2 cents point-of-view for free to
all of you ...

A lot af satisfaction with HP Proliant MicroServer from the first GEN6 (AMD
NEON) to the 1-year old MicroServer Gen10 X3216 (CentOS6/7/8) so I think
yours is the right choice!

In /boot/efi/ (mounted from the first partition of the first GPT disk) you
only have the grub2 efi binary, not the vmlinuz kernel or initrd image or
the grub.cfg itself ...

To be more precise a grub.cfg file exists there but it's only a static file
which has an entry to find the right one using the uuid fingerprint

*cat \EFI\ubuntu\grub.cfg*search.fs_uuid
d9f44ffb-3cb8-4783-8928-0123e5d8a149 root
set prefix=($root)'/@/boot/grub'
configfile $prefix/grub.cfg

Using an md1 software raid mirror for this FAT32 (ESP) partition is not
safe IF you use it outside of the linux environment (because the mirror
will became corrupted at the first write the other OSes will do on this

It's better to setup a separated /boot partition (yes, here an md1 linux
software raid mirror is OK) which the grub2 bootloader can manage correctly
(be sure grub2 can access his modules to understand and manage this
LVM/RAID : mdraid09,mdraid1x,lvm.mod [1] [2]

insmod raid
#    and load the related `mdraid' module `mdraid09' for RAID arrays
with version 0.9 metadata, and `mdraid1x' for arrays with version 1.x
     insmod mdraid09
     set root=(md0p1)
#    or the following for an unpartitioned RAID array
     set root=(md0)

IMHO installing ex-novo is the easiest path with setup that puts all the
things correctly, building the right initramfs and putting the correct
entry in grub.cfg for the modules needed to manage raid/lvm...
To be honest I don't know how the anaconda installer manage the /dev/sda1
ESP/FAT32/EFI partitions (I'd like it clones this efi partition to the 2nd
disk, but i think it will leave /dev/sdb1 partition empty)

To understand better how GRUB2 works i've looked here : [3] [4] [5]

Happy hacking


[1] : https://unix.stackexchange.com/questions/187236/grub2-lvm2-raid1-boot
[2] : https://wiki.gentoo.org/wiki/GRUB/Advanced_storage
[3] : https://www.gnu.org/software/grub/manual/grub/grub.html
[4] :
[5] : https://wiki.archlinux.org/title/GRUB