DISCUSSION: How to boot from RAID using "dmraid"

Erik_FL · 10-03-2006, 01:22 PM

This thread is to discuss the article titled:
How to boot from RAID using "dmraid"

Quote:

I had to use dmraid to find and map the RAID sets with the device-mapper in Linux. Once I got dmraid to work, my problem was how to make a working initrd RAM disk image to boot Slackware Linux. It turned out to be quite a bit more complicated than I expected. I had to create a new "linuxrc" script to map the RAID volumes and mount the root filesystem. I also had to write a script to include additional files in the initrd RAM disk image. Here is the new "linuxrc" script. [CODE] # Boot parameters: # real_root=rootdev Replace "rootdev" with real root device # root_fs=rootfs Replace "rootfs" with real root filesystem type

maxkukartsev · 01-04-2010, 12:11 AM

Hi Erik_FL,

You said you had to do a "native" GRUB installation from BIOS since GRUB couldn't recognize your RAID array in linux.

You could get a linux GRUB installation working by supplying a custom device map:

Code:

$ cat device.map

(hd0) /dev/mapper/isw_cafaadgife_RAID0

Here I used the base RAID array device, as opposed to the individual isw_cafaadgife_RAID01, isw_cafaadgife_RAID02, and isw_cafaadgife_RAID03, which correspond to RAID partitions (hd0,0), (hd0,1), and (hd0,2) respectively.

Running grub with this device map, everything works out nicely:

Code:

grub --device-map=device.map