Raid 1 in HPE Gen10

[Robert Moskowitz]

On 6/19/25 7:48 AM, Sam Varshavchik wrote:
> Robert Moskowitz via ubuntu-users writes:
>
>> I have an HPE Gen 10 with 4 4TB drives that has been sitting for 2 
>> years for me to figure out how to get RAID working.
>>
>> Now that I am working with Ubuntu, it almost makes sense, but I am 
>> not there.  Yet.
>>
>> Seems I have to go into custom setup for the drives.
>>
>> So far I have only taken 2 drives into a RAID1 config and the other 
>> two into an LVM
>>
>> Once I selected Raid and put the two drives in it, I was only offered 
>> formatting as EXT4 for /
>>
>> I am being told I need a boot partition.  Of course.
>>
>> So is there any decent guide for this?
>
> It is certainly possible because I have done this exact same thing, 
> but using mdraid rather than any hardware-based RAID. A lot of ink has 
> been spilled about this, over the years, but the capsule summary is 
> that mdraid over the long term will fare better. You can pull the 
> disks and drop them into another box and it'll just work, for example. 
> You can't do this with hardware RAID, without also installing 
> identical hardware, too. And if your hardware RAID card gives up the 
> magic smoke you're SOL, unti you can find an identical replacement.

I like the sound of this.  I have a long history of pulling a drive out 
of one box and placing it another and getting on with life. Also allowed 
me to upgrade to better processor/more memory without rebuilding the drive.

>
> I basically followed this:
>
> https://askubuntu.com/questions/1299978/

Maybe this will explain opening up terminal...

>
> but skipped some of the fluff up front. The capsule summary is:
>
> 1) Boot the installer, open a terminal shell
>
> 2) apt update, apt install mdadm

where in the installer do you get the option to open a shell?


and it seems that the Ubuntu 24 is offering me some tools for setting up 
the RAID.

>
> 3) Use fdisk (or sgdisk) to partition both drives, then use mdadm to 
> assemble them into RAID arrays.

How long has it been since I used fdisk for this?  I long ago switched 
to parted.  But even that I have to read my crib notes.

> This is where I wish I've done something different than the guide, 
> which basically tells you that the EFI boot partition is SOL, as far 
> as mdraid goes, and gives you marching orders to just create a 
> non-RAID partition on both disks, use the one on the boot drive for 
> the UEFI partition, set up some automation to dd it to the other 
> drive's partition, and use efibootmgr to include both disks as 
> bootable devices.
>
> Since then, I've learned that it should be possible to use mdraid for 
> the EFI boot partition by formatting it as mdraid 1.0 instead of 
> mdraid 1.1 (still need to fiddle with efibootmgr). It just so happens 
> that this is exactly the situation on my other box running Fedora, 
> which has no issues with the efi boot partition on mdraid (Fedora's 
> installer directly supported installation to mdraid for a very long 
> time, at least a decade). I'll try that next time.

This box, and many of its ilk has an internal slot for USB or SD device 
where you can place the boot loader.  I figure that after each new 
kernel I can dd that partition to a file on the RAID HD for safe keeping.

>
> 3) Start the ubuntu installer. It'll be slightly confused and list 
> both the physical partitions and the RAID partition together, as 
> installation targets. Be sure to select the right partitions 
> (disclaimer, this was the story in Ubuntu 20, current experience might 
> vary).

Thank you for sharing your experiences.  I will definitely check out 
that guide.

>
>