8.0 amd64 - Royally screwed up MBR (My own fault)

Henrik Hudson lists at rhavenn.net
Wed Mar 24 22:33:11 UTC 2010

On Wed, 24 Mar 2010, Gene wrote:

> Greetings - (not a draft notice)
> First thanks to those who responded to my previous question.
> Next...
> I was attempting to install 8.0 amd64 w/ZFS. I used instructions from the wiki
> and when I had trouble, I decided to beat a strategic retreat and just do a
> "vanilla" install. Problem was that either fdisk didn't recognize the mbr
> after all the 'gpart create'-ing or simply couldn't start newfs. (Something
> about not being able to find an initial inode.) I figured 'gpart destroy ad0'
> might fix things but no such luck. fdisk -I ad0 also errors out saying "unable
> to locate class".
> Does anyone know of a simple (brute force?) way to restore simple. standard
> MBRs without having to resort to a hex editor? (I will if I have to, but I'd
> rather not.)

This will wipe the MBR: dd if=/dev/zero of=/dev/sdb bs=446 count=1

replace of=/dev/sdb  without whatever /dev/sd? you need.

Henrik Hudson
lists at rhavenn.net
"God, root, what is difference?" Pitr; UF 

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