Re: Booting from raid1 -- md: invalid raid superblock magic on sdb1

[Bill Davidsen <davidsen@tmr.com>]

David M. Strang wrote:

> I've read, and read, and read -- and I'm still not having ANY luck 
> booting completely from a raid1 device.
>
> This is my setup...
>
> sda1 is booting, working great. I'm attempting to transition to a 
> bootable raid1.
>
> sdb1 is a 400GB partition -- it is type FD.
>
> Disk /dev/sdb: 400.0 GB, 400088457216 bytes
> 2 heads, 4 sectors/track, 97677846 cylinders
> Units = cylinders of 8 * 512 = 4096 bytes
>
>   Device Boot      Start         End      Blocks   Id  System
> /dev/sdb1               1    97677846   390711382   fd  Linux raid 
> autodetect
>
> I have created my raid1 mirror with the following command:
>
> mdadm --create /dev/md_d0 -e1 -ap --level=1 --raid-devices=2 
> missing,/dev/sdb1
>
> The raid created correctly, I then partitioned md_d0 to match sda1. 

I hope that's a typo... you need to partition sdb, not the md_d0 raid 
device.

-- 
bill davidsen <davidsen@tmr.com>
  CTO TMR Associates, Inc
  Doing interesting things with small computers since 1979