Re: [9fans] something evil happening when partitioning a hdd with the plan9 installer

[John Stalker <stalker@maths.tcd.ie>]

John,

Several things are odd about this.  I do in fact have plan9 installed
on an extended partition on a Dell laptop, so I know it can be done.
Here a few things to check:

  1) Do your BIOS, linux and plan9 all agree about the number of
  cylinders, heads and sectors on the disk?  I once had similar
  problems when NetBSD and FreeBSD saw different disk geometries.
  On reboot the disk appeared to have been wiped.  In fact,
  everything was still there, but the partition table in the
  MBR was messed up.

  2) Whose boot loader are you using?  Personally, I use GAG.  Noone
  ever seems to recommend it, but I've never had any problems.  It
  can boot from extended partitions or other disks.

  3) Is your disk IDE or SATA?  Plan9 still has problems with SATA
  sometimes.

John

> Hi all!
> This is my first message, so please don't bash me too hard for my
> ignorance!
> I just got a shiny new dell inspiron 640m notebook. It has a core2duo
> processor, 2 gigs of RAM and a 120gig hdd. The first thing I did, after
> installing linux on it was to try plan9. I was amazed that the
> installer actually started up on this brand new system, but eh, plan9
> is a modern operating system, I guess ;)
> The problem was that dell shipped that laptop with more than 12 gigs
> reserved for the windows restore thing and other various stuff on 4
> partitions, so I hardly had any primary partitions to use. My first try
> was to install plan9 on a secondary partition (yes, rtfm!!!), which was
> a very stupid thing to do, nevertheless the partition table got messed
> with really bad. I mean, I could hardly recover my linux root partition
> from the 6 partitions I had on the disk. The rest got wiped.
> Okay, I thought, what a blunder, I wont miss that one again. So I wiped
> my disk clean, and repartitioned now without all the dell partitions, so
> I had my first partition reserved for plan9. I just got to the point of
> installing plan9 on the machine again, so I loaded the plan9 cd in and
> booted it (from april 4th 2007). I created the plan9 partition at the
> beginning, where I reserved 3 gigs for it when reinstalling my system.
> Okay, I thought, I got through the partitioning part with no problem, I
> also subdivided my partition and mounted the fossil partition. Then I
> thought I would check out what happened, and reboot my system into
> linux. I know cfdisk is one of the most sensitive partitioning
> tools, so I fired it up, and, to my joy, it spat an error message at
> me. Actually, the same one as the one I got before.The error was
> partition 4 extends past end of disk. I think partition 4 was my
> extended partition, but I did not really see anything strange, I
> checked the cylinders, but it looked like partition 4's end was the
> last cylinder of the disk, so I didn't really understand, the same
> thing happened before, when I installed it on an extended partition:
> the partition table lloked fine, but cfdisk would complain, and my
> system would get unbootable.
> Sorry for the length of the message.
> cheers!
> John
-- 
John Stalker
School of Mathematics
Trinity College Dublin
tel +353 1 896 1983
fax +353 1 896 2282