8.3-BETA1 installation problem

[Michael Powell]

Warren Block wrote:

> On Wed, 22 Feb 2012, Omer Faruk SEN wrote:
> 
>> I am trying to install FreeBSD 8.3-BETA1 to a system with ssd disk
>> recognized as ad6. At fixit mode i can dd device but at installer
>> (sysinstall) when I configured disk and using "w" installer is unable to
>> format devices stating that
>>
>> "Unable to find device node for /dev/ad6s1b in dev. The creation of file
>> systems will be aborted"
>>
>> any suggestion on what may be the reason for that or is it a bug on
>> installer
> 
> Using "W"rite is one of the causes for that.  Don't Write, just choose
> Quit after making selections.
> 
> (There are other causes, like old partitioning information on the disk.
> Removing that with gpart destroy or just dd-ing zeros over it is the
> cure in that case.)

If you need to clear the old MBR the "old way", use a LiveFS or Fixit shell 
and do this (as root):

sysctl kern.geom.debugflags=16  and:

dd if=/dev/zero of=/dev/adx oseek=1 bs=512 count=1 

where x equals your drive number. This will zero out any old MBR.

A time or two when I've seen this error this fixed it up and the install 
proceeds as normal. As Warren said before, don't use the "W", just Q and  
sysinstall will queue and issue all the commands at a later point.

-Mike