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

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

One more thought.  Perhaps your partition numbering is getting screwed
up.  Linux, and other UNIX clones, will get confused if you insert
new extended partitions, because you bump up the numbers of those that
follow.  Plan9 avoids this silliness for the most part, but has another
annoying habit.  If, for some reason, your partitions are out of order on
the disk, e.g. the third one is before the second, plan9 will "helpfully"
reorder them in the partition table in the MBR.  This isn't actually
wrong, but it can certainly be hard to diagnose the resulting problems
if you don't know that it is happening.

> 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