disk utility benchmarking problems

[Marius Gedminas]

On Thu, Nov 24, 2011 at 08:55:08AM -0500, Alan McKay wrote:
> I am running 11.04 and go into the disk utility and select my USB
> drive because I want to run a benchmark on it with the benchmarking
> feature of the disk util.
> 
> At first it told me the disk had to have no partitions so I wiped them
> and tried again.
> 
> Now it says it fails because "the disk seems to have usage raid -
> write benchmarking requires the disk to be completely empty"
> 
> So I google that and check this list.  In google I found the same
> problem and they fixed it by using dd to wipe the MBR
> 
> dd if=/dev/zero of=/dev/sdb bs=512 count=1
> 
> So I tried that and still get the same error.  Even if I write zeros
> for a much longer time than just count=1

I think the RAID metadata lives somewhere near the end of the device, not at the
beginning.

Try mdadm --zero-superblock /dev/sdb

Marius Gedminas
-- 
We'll show a small example here with one user calling another. (Under
international treaties describing technical papers these users must be called
"Alice" and "Bob".)
        -- Anthony Baxter
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 190 bytes
Desc: Digital signature
URL: <https://lists.ubuntu.com/archives/ubuntu-users/attachments/20111124/c2ef220f/attachment.sig>