gpg: failed to create temporary file '/var/lib/lurker/.#lk0x56d08100.hantslug.org.uk.14363': Permission denied
gpg: keyblock resource '/var/lib/lurker/pubring.gpg': Permission denied
gpg: Signature made Sat Mar 28 16:05:39 2009 GMT
gpg: using DSA key 20ACB3BE515C238D
gpg: Can't check signature: No public key
On Sat, Mar 28, 2009 at 03:13:08PM -0000, Rob Malpass wrote:
> Hi all
>
> Trying to setup raid (on Ubuntu 8.1) with the command
>
> mdadm --assemble /dev/md0 /dev/sdb /dev/sdc
>
> and receiving the error no recognisable superblock on /dev/sdb
>
> The thing is I can mount both drives having formatted them to ext3 previously. I don't know what superblock means but I thought it meant that the drive's not formatted - which it obviously is if I can mount and read/write to it. I must be doing something obvious wrong - but can't see what. To the best of my knowledge I've followed the guide at
--assemble constructs a RAID array from existing RAID elements. You
probably want --create, which will turn the devices into RAID elements
first. I'm not sure if this operation is destructive to the contents
of the drive, so if you've got a filesystem with data already on there
that you want to keep, don't use it until you've read up some more. (I
think it isn't, but you have to be careful about the way in which you
construct the RAID array).
In general, a "superblock" is an area of storage medium that
contains information about the rest of the medium -- for a filesystem,
this might be the location of the root directory and the allocation
tables; for a RAID element, it contains the UUID of the RAID device it
comes from, its role in that device, and probably some information
about the other elements in the RAID device.
Effectively, not having a RAID superblock means that the device
*isn't* formatted, but it's not-formatted for RAID, rather than being
not-formatted for the filesystem.
Hugo.
--
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
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