On Mon, Feb 08, 2010 at 04:25:17AM +0200, Nikos Chantziaras wrote:
> You said that Google didn't help, but still, I've found some info about
> it. In short, I've found two things:
>
> a) "cfdisk" might work while "fdisk" does not.

Interesting. My personal experience has been the opposite: cfdisk
writes (and demands) better formed partition tables, so sometimes crap
that fdisk can read/write will not work with cfdisk. But of course,
YMMV. Since we are bringing up alternative fdisk programs, what about
sfdisk? I wouldn't put money on it, but it won't hurt to try.

W
--
Willie W. Wong wwong@math.princeton.edu
Data aequatione quotcunque fluentes quantitae involvente fluxiones invenire
et vice versa ~~~ I. Newton

Am Montag 08 Februar 2010 01:27:59 schrieb Peter Humphrey:
> Hello again List,
>
> $ sudo fdisk -l
>
> Unable to seek on /dev/sda
>
> What am I to make of this? The system runs ok, but apparently the
> underlying disk subsystem isn't happy. This box has only the one disk at
> the moment. Google doesn't help.
>
> The box is a new Armari system with an Asus P7P55D motherboard and a
> Samsung Spinpoint F3 1TB SATA II hdd.
>

Having read the thread, there are three things that come to my mind:

1) Have you tried to read from the disk at block zero, i.e. try something like
dd if=/dev/sda of=/dev/null bs=512 count=1024
This should read half a megabyte from the disk and for your hardisk be
finsihed as soon you release the enter key ...
Errors? and messages in dmsg?

2) The dmesg-output you mailed contains a call-trace about calgary. AFAIK
calgary is a IOmmu. Have you tried to disable it (try something like appending
iommu=none to your kernel commandline).
Have you looked for a bios upgrade? maybe you can get rid of the "broken bios"
messages this way.

3) A long time ago, there was a bios option for bootsector-protection, I've
never tried this, and I also don't have any idea whether linux sees that in
any way. If there is such an option, disable it.

Greetings
Alex

On Sun, Feb 7, 2010 at 6:16 PM, Peter Humphrey <peter@humphrey.ukfsn.org> wrote:
> On Monday 08 February 2010 01:27:33 Mark Knecht wrote:
>
>> sorry to have forgotten is but simply do
>>
>> df
>>
>> and see what it says is mounted
>
> $ df
> Filesystem * * * * * *Size *Used Avail Use% Mounted on
> rootfs * * * * * * * * 60G * 25G * 32G *44% /
> /dev/root * * * * * * *60G * 25G * 32G *44% /
> rc-svcdir * * * * * * 1.0M *108K *916K *11% /lib64/rc/init.d
> udev * * * * * * * * * 10M *144K *9.9M * 2% /dev
> shm * * * * * * * * * 2.0G * * 0 *2.0G * 0% /dev/shm
> /dev/sda6 * * * * * * *40G *6.4G * 32G *17% /home
> /dev/sda7 * * * * * * *61G * 23G * 36G *39% /home/prh/common
> tmpfs * * * * * * * * 9.0G *1.8M *9.0G * 1% /tmp
>
> Now, ever since I upgraded to openrc (by setting ACCEPT_KEYWORDS=~amd64
> when I installed this system) my root partition has not been shown as a
> physical partition. I decided to let it go for the time being.
>
> --
> Rgds
> Peter.
>
>

Is this some sort of LVM thing creeping in? I don't use it but I see
signs of it starting to show up on my systems like something is making
it come in with new profiles or something.

I don't know how LVM works but I assume that rootfs and /dev/root have
something to do with your main file system? I rebuilt new hardware for
my dad yesterday using the default sda1/2/3 setup from the Gentoo
AMD64 Install Guide and I see the following:

gandalf ~ # df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda3 103212320 5041116 92928324 6% /
udev 10240 164 10076 2% /dev
shm 1925772 0 1925772 0% /dev/shm
gandalf ~ # cat /proc/partitions
major minor #blocks name

8 0 976762584 sda
8 1 102343 sda1
8 2 8388608 sda2
8 3 104857600 sda3
gandalf ~ #

Did you intend to have 3 100MB partitions at the start of your drive
and then everything else inside of an extended partition? It's not
wrong - it was just unexpected for me.

Is yours a 1-Terabyte drive?

On Mon, Feb 8, 2010 at 8:20 AM, Alexander Puchmayr
<alexander.puchmayr@linznet.at> wrote:
> 3) A long time ago, there was a bios option for bootsector-protection, I've
> never tried this, and I also don't have any idea whether linux sees that in
> any way. If there is such an option, disable it.

Sometimes referred to as "virus protection" or "anti-virus" in some
bios versions too.

When is a disk not a disk?


According to Dell: when you source it from a 3rd-party.

http://lists.us.dell.com/pipermail/linux-poweredge/2010-February/041274.html
<http://tinyurl.com/yer7n9o>

Stroller.

On Monday 08 February 2010 15:02:51 Mark Knecht wrote:

> Did you intend to have 3 100MB partitions at the start of your drive
> and then everything else inside of an extended partition? It's not
> wrong - it was just unexpected for me.

I did, but I think I'll revert to just a single boot partition. The
other two little ones were for other distros' boot directories, so that
installing them wouldn't clobber my Gentoo boot - the latest Ubuntu uses
grub-2, for instance, which I don't want mixed with grub-1.

> Is yours a 1-Terabyte drive?

Yes. Vast overkill for what I need it for, but it seems normal nowadays.

--
Rgds
Peter.

On Monday 08 February 2010 02:25:17 Nikos Chantziaras wrote:

> b) You have a corrupted partition table that you can try to repair
> with the "testdisk" tool (after you make a full backup of your
> disk.)

That seems to have been it. Testdisk did indeed write a new partition
table, minus one of the partitions which it insisted on deleting so I
suppose something was wrong with it.

After much time taking and restoring backups my main system is now
running again and i can run fdisk.

I'm surprised at this, because a seek error sounds uncomfortably like a
hardware problem to me. Maybe some particular error in the partition
table confused fdisk and cfdisk.

Anyway, thanks for the help, Nikos and all those who offered it.

--
Rgds
Peter.

On Mon, 8 Feb 2010 07:02:51 -0800, Mark Knecht wrote:

> Is this some sort of LVM thing creeping in? I don't use it but I see
> signs of it starting to show up on my systems like something is making
> it come in with new profiles or something.
>
> I don't know how LVM works but I assume that rootfs and /dev/root have
> something to do with your main file system?

LVM can't just turn up with a profile change, you need to allocate
partitions to it, create volume groups, create volumes in them, put
filesystems on the volumes and so on. It doesn't just happen.

/dev/root is just a symlink to the real device containing the root
partition. ISTR it came in with openrc.


--
Neil Bothwick

On Mon, Feb 8, 2010 at 9:02 AM, Mark Knecht <markknecht@gmail.com> wrote:
> Is this some sort of LVM thing creeping in? I don't use it but I see
> signs of it starting to show up on my systems like something is making
> it come in with new profiles or something.

Some lvm tools/packages have replaced others that don't have "lvm" in
the name, so maybe that's what you have seen. They aren't solely used
for LVM-related things, though