Fake RAID 1 problem on Debian 8.5

vitronix · 08-08-2016, 01:37 PM

Hello good poeple of LinuxQuestions,

I recently bought a Asus P9D-C server mainboard.
It has two 2TB western digital hard disks.
Processor is an i3 64-bit.
The BIOS supports RAID 1.
It has a mpt2sas controller.
This approach is known as fake raid.
I followed these instructions:

https://wiki.debian.org/DebianInstaller/SataRaid

I have read somewhere that my kernel has build in support for the mpt2sas controller.

When I execute:

Code:

grub-install /dev/mapper/isw_egcjjfef_STORAGE

The output is:

Code:

Installing for i386 platform
Installation finished No error reported.

When I reboot i get a message:

Code:

modprobe: module dm-raid45 not found in modules.dep

A start job is running for /dev/mapper/isw_egcjjfef_STORAGE

Eventually I get the message:

Code:

Welcome to emergency mode!

I can give the root password and log in.
I have access to the filesystem.
My guess is that some kernel module isn't loaded.

Can anyone please help I'm getting pretty desperate :-(

Thanks in advance,

vitronix

jefro · 08-08-2016, 04:30 PM

Do you want to undo your changes?

I'd boot to some live media and get your data off/backup to start.

You don't really have to use the fake raid as a raid do you? There are better ways maybe. Stupid fake raid may or may not work on next update. I might consider using a different solution like lvm or btrfs.

syg00 · 08-08-2016, 06:46 PM

It looks like the OP didn't follow the instructions completely (as in steps 7-15) by rebooting into recovery using the live media to fix grub. I use neither Debian nor fake-raid, but the instructions look ok.

I would also prefer mdadm over fake-raid, but it's the OPs machinery. (Edit:) - have a read of what the Linux RAID (i.e. mdadm) folks think of using fake-raid in the "Hardware RAID" section here.