Re: Partitioning Disks on DS20

[Chris Kloiber <chris_kloiber suth com>]

John Helly wrote:
> 
> Hi greg.
> I wish I was running it. Unfortunately I don't see any c partition.  Both
> the Unix-level partition table AND the BSD partition table appear to be
> empty.  Do I have to do something special to see the BSD c partition?
> cheers.
> 
> > -----Original Message-----
> > From: Greg Lindahl [mailto:lindahl@cs.virginia.edu]
> > Sent: Monday, October 04, 1999 6:45 PM
> > To: axp-list@redhat.com
> > Subject: Re: Partitioning Disks on DS20
> >
> >
> > > fdisk appears to create partition extents with cylinder numbers I do not
> > > enter.  For example, if I try to create BSD partition a from
> > 3-50 it does
> > > that.  However, if I try to create partition b from 51-1024 it
> > assigns to
> > > some inconsistent range.
> >
> > If I recall correctly, I had a similar problem with a disk where I
> > hadn't deleted the existing "c" partition, which took the entire
> > disk. After we deleted "c", life was better. This is only a feature of
> > BSD disk labels and fdisk; normal disklabels don't function like
> > that. I wish Compaq would teach SRM about fdisk-style disk labels...
> >
> > Glad to see SDSC is finally running a decent OS on those alphas ;-)
> > ;-)
> >
> > -- g

I have noticed some bizzarre behavior from the BSD disk labeling portion
of fdisk as well, but I found a way to fix it. My Multia is about as far
from a DS 20 as you can get and still be talking Alpha, but I found that
if you are creating partitions and see asterisks where the cylinders are
(say you chose a partition from cyl 2 to cyl 4- and when you print the
partition table you see (1*-2*)) you can fix this by exiting fdisk and
typing:

# cat /dev/zero > /tmp/sda bs=512 count=2
(this assumes there is nothing on the disk you want :-)

That will totally blank the MBR and the partition table. When you
re-enter fdisk it will be slightly confused, but will redetect the
geometry of the drive and warn you that there is no vakid disklabel. It
then asks if you want to create a new label (yes!). Then most fo the
weirdness will be solved.

Your mileage may vary.

Chris Kloiber