dd command to clear start of harddrive

[Nigel Henry]

This is not directly Fedora related.

I connect to the Internet through my Smoothwall, and a serial modem. Recently 
the machine that the Smoothwall is running on has been playing up. Harddrive 
spinning up and down. I have another older machine (1.33GHz, 64MB RAM, and 
6GB harddrive) which had Win 2000 pro on it, and was trying to install a 
backup Smoothwall on it. The Smoothwall installs ok, and lilo is installed, 
but when I reboot the BIOS does the memory check, and all I get next is half 
a screenfull of "40's" printed out. they remain for a few seconds, then I 
just get a prompt that I can't do anything with.

I am wondering if something has been left behind on the harddrive from the Win 
2000 install, that linux has not been able to remove.

I've seen a few times a dd command that can get rid of stuff at the start of a 
drive, but stupidly have not written down the info.

Could someone kindly give the required dd command to make sure that the 
harddrive is clear of all data.

The machine won't boot off cd, but using smart boot manager on a floppy, I can 
get Finnix booted up on it, and work off the CLI.

Thanks for any help from the list.

Nigel.

[Andy Green]

Somebody in the thread at some point said:
>  This is not directly Fedora related.
>  
>  I connect to the Internet through my Smoothwall, and a serial modem. Recently 
>  the machine that the Smoothwall is running on has been playing up. Harddrive 
>  spinning up and down. I have another older machine (1.33GHz, 64MB RAM, and 
>  6GB harddrive) which had Win 2000 pro on it, and was trying to install a 
>  backup Smoothwall on it. The Smoothwall installs ok, and lilo is installed, 
>  but when I reboot the BIOS does the memory check, and all I get next is half 
>  a screenfull of "40's" printed out. they remain for a few seconds, then I 
>  just get a prompt that I can't do anything with.
>  
>  I am wondering if something has been left behind on the harddrive from the Win 
>  2000 install, that linux has not been able to remove.
>  
>  I've seen a few times a dd command that can get rid of stuff at the start of a 
>  drive, but stupidly have not written down the info.
>  
>  Could someone kindly give the required dd command to make sure that the 
>  harddrive is clear of all data. 
You can take a dump on it like this -- make sure everything from sdbX is
unmounted --

# dd if=/dev/zero of=/dev/sdb bs=1024 count=5000

for example that will crap on the first 5MBytes on your /dev/sdb drive,
erasing the partition table, bootloader and probably the start of the
first partition.  Obviously take care to change sdb to your actual drive.

You'll need to run partprobe and fdisk it afterwards and reformat as usual.

-Andy

[John Summerfield]

Nigel Henry wrote:
>  This is not directly Fedora related.
>  
>  I connect to the Internet through my Smoothwall, and a serial modem. Recently 
>  the machine that the Smoothwall is running on has been playing up. Harddrive 
>  spinning up and down. I have another older machine (1.33GHz, 64MB RAM, and 
>  6GB harddrive) which had Win 2000 pro on it, and was trying to install a 
>  backup Smoothwall on it. The Smoothwall installs ok, and lilo is installed, 
>  but when I reboot the BIOS does the memory check, and all I get next is half 
>  a screenfull of "40's" printed out. they remain for a few seconds, then I 
>  just get a prompt that I can't do anything with.
>  
>  I am wondering if something has been left behind on the harddrive from the Win 
>  2000 install, that linux has not been able to remove. 
Almost certainly that is not the problem,

You need to read the lilo documentation, it will probably explain to you 
exactly what is wrong.



-- 

Cheers
John

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[Nigel Henry]

On Thursday 25 October 2007 01:23, John Summerfield wrote:
>  Nigel Henry wrote:
>  > This is not directly Fedora related.
>  >
>  > I connect to the Internet through my Smoothwall, and a serial modem.
>  > Recently the machine that the Smoothwall is running on has been playing
>  > up. Harddrive spinning up and down. I have another older machine
>  > (1.33GHz, 64MB RAM, and 6GB harddrive) which had Win 2000 pro on it, and
>  > was trying to install a backup Smoothwall on it. The Smoothwall installs
>  > ok, and lilo is installed, but when I reboot the BIOS does the memory
>  > check, and all I get next is half a screenfull of "40's" printed out.
>  > they remain for a few seconds, then I just get a prompt that I can't do
>  > anything with.
>  >
>  > I am wondering if something has been left behind on the harddrive from
>  > the Win 2000 install, that linux has not been able to remove.
>
>  Almost certainly that is not the problem,
>
>  You need to read the lilo documentation, it will probably explain to you
>  exactly what is wrong. 
>  Cheers
>  John 
Thanks to Andy for the dd syntax, but sadly, although it cleared the start of 
the drive, I still couldn't get the Smoothwall to boot up post install, just 
an "L" followed by a string of 40's after the BIOS memory check. All a bit 
weird, as when I bought the machine about 4 years ago when I first started 
with computers, it had Win 98 on it, and that worked ok. I passed the machine 
onto my son, and he somehow got Win 2000 pro installed on it. I know that was 
booting ok, because I tried it. It got as far as wanting the password to get 
in, but as I don't know his password I couldn't progress further, but at 
least it was booting, so it doesn't seem to be a problem with booting from 
the harddrive. 

Could a failing cmos battery cause this sort of problem? I cycled down to town 
today, but forgot to buy a new one.

John. Lilo is possibly the problem, but I can't see how to re-install it in 
the MBR. Saying that though, on the other machine where the Smoothwall is 
working ok, there is no problem, and I couldn't be posting this if lilo was 
screwed up.

Perhaps the machine is just a piece of junk, and needs to be sent to the 
nearest dumpster, but I do like to try and resolve problems, before trashing 
what might be a useable machine.

I booted up the problem machine with the Smoothwall installed on it using 
Finnix. Running fdisk -l showed the same output as ssh'ing into my smoothwall 
that's up and running, but couldn't find a way of chrooting into the 
Smoothwall partitions from Finnix. perhaps I'm a bit out of my depth. I was 
looking to rerun /sbin/lilo just to see if it hadn't been installed in the 
MBR, and maybe that was the problem which resulted in the "L", and half a 
screen of 40's when booting up.

Perhaps I should just forget about the problem machine, and trying to install 
Smoothwall on it. My current running Smoothwall has settled down, and I can 
access the Internet from my Fedora, Debian, and other distros through it.

Thanks for the help guys.

Nigel.

[John Summerfield]

Nigel Henry wrote:
>  On Thursday 25 October 2007 01:23, John Summerfield wrote:
> > Nigel Henry wrote:
> >> This is not directly Fedora related.
> >>
> >> I connect to the Internet through my Smoothwall, and a serial modem.
> >> Recently the machine that the Smoothwall is running on has been playing
> >> up. Harddrive spinning up and down. I have another older machine
> >> (1.33GHz, 64MB RAM, and 6GB harddrive) which had Win 2000 pro on it, and
> >> was trying to install a backup Smoothwall on it. The Smoothwall installs
> >> ok, and lilo is installed, but when I reboot the BIOS does the memory
> >> check, and all I get next is half a screenfull of "40's" printed
> out.
> >> they remain for a few seconds, then I just get a prompt that I can't do
> >> anything with.
> >>
> >> I am wondering if something has been left behind on the harddrive from
> >> the Win 2000 install, that linux has not been able to remove.
> > Almost certainly that is not the problem,
> >
> > You need to read the lilo documentation, it will probably explain to you
> > exactly what is wrong.
>  
> > Cheers
> > John
>  
>  Thanks to Andy for the dd syntax, but sadly, although it cleared the start of 
>  the drive, I still couldn't get the Smoothwall to boot up post install, just 
>  an "L" followed by a string of 40's after the BIOS memory check. All a bit 
As I said.

>  weird, as when I bought the machine about 4 years ago when I first
> started 
>  with computers, it had Win 98 on it, and that worked ok. I passed the machine 
>  onto my son, and he somehow got Win 2000 pro installed on it. I know that was 
>  booting ok, because I tried it. It got as far as wanting the password to get 
>  in, but as I don't know his password I couldn't progress further, but at 
>  least it was booting, so it doesn't seem to be a problem with booting from 
>  the harddrive. 
>  
>  Could a failing cmos battery cause this sort of problem? I cycled down to town 
>  today, but forgot to buy a new one.
>  
>  John. Lilo is possibly the problem, but I can't see how to re-install it in 
>  the MBR. Saying that though, on the other machine where the Smoothwall is 
>  working ok, there is no problem, and I couldn't be posting this if lilo was 
>  screwed up. 
I don't care whether the other machine works, it's irrelevant.

Read the freaking documentation.



-- 

Cheers
John

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[Mikkel]

Nigel Henry wrote:
>  
>  Thanks to Andy for the dd syntax, but sadly, although it cleared the start of 
>  the drive, I still couldn't get the Smoothwall to boot up post install, just 
>  an "L" followed by a string of 40's after the BIOS memory check. All a bit
>
>  weird, as when I bought the machine about 4 years ago when I first started 
>  with computers, it had Win 98 on it, and that worked ok. I passed the machine 
>  onto my son, and he somehow got Win 2000 pro installed on it. I know that was 
>  booting ok, because I tried it. It got as far as wanting the password to get 
>  in, but as I don't know his password I couldn't progress further, but at 
>  least it was booting, so it doesn't seem to be a problem with booting from 
>  the harddrive. 
>  
>   
You should probably read the troubleshooting section of LILO. But I
suspect the problem is in the BIOS of the machine you are trying to
use. I suspect that you are trying to read part of the drive that
the BIOS of that machine can not access. An updated BIOS may help.
If not, using a /boot partition at the start of the drive will help.
Remember, both LILO and Grub use the BIOS to access the hard drive.

Depending on the version of LILO, there may be an option to use LBA
addressing that sometimes also helps. I believe it is automatically
used in the latest versions, but I could be wrong.

One way to see if it is a BIOS problem is to try using the same
drive in a more modern machine. If it boots without problems there,
then it is a good indication that it is a BIOS problem, or that you
are using 2 different settings for the hard drive. I have run into
problems in that past where one machine used LBA, and another used
the LARGE mode, or didn't support the newer modes, and you could not
boot from the drive in the older machine anfer installing from the
newer machine, even if they used the same processor.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

[Nigel Henry]

On Friday 26 October 2007 02:59, Mikkel L. Ellertson wrote:
>  Nigel Henry wrote:
>  > Thanks to Andy for the dd syntax, but sadly, although it cleared the
>  > start of the drive, I still couldn't get the Smoothwall to boot up post
>  > install, just an "L" followed by a string of 40's after the BIOS
> memory
>  > check. All a bit weird, as when I bought the machine about 4 years ago
>  > when I first started with computers, it had Win 98 on it, and that worked
>  > ok. I passed the machine onto my son, and he somehow got Win 2000 pro
>  > installed on it. I know that was booting ok, because I tried it. It got
>  > as far as wanting the password to get in, but as I don't know his
>  > password I couldn't progress further, but at least it was booting, so it
>  > doesn't seem to be a problem with booting from the harddrive.
>
>  You should probably read the troubleshooting section of LILO. But I
>  suspect the problem is in the BIOS of the machine you are trying to
>  use. I suspect that you are trying to read part of the drive that
>  the BIOS of that machine can not access. An updated BIOS may help.
>  If not, using a /boot partition at the start of the drive will help.
>  Remember, both LILO and Grub use the BIOS to access the hard drive. 
Hi Mikkel. Sorry for the delay in my reply. I've been reading, reading, and 
more reading about LILO. I use LILO on my Debian installs, and havn't had 
problems with it. I believe you're right in it being a BIOS problem. I've 
been on the site that has docs, specs, etc for this AST Bravo MS 5133 
machine, and it was shipped with a 1.2GB HDD, and Win95, with possibilities 
of a 2GB one being used (1024 cyl limit in the BIOS setup). The drive my son 
had Win 2000 pro on is a 6GB one (13328 cyl). Quite how he got it set up, 
I've no idea, but I know it booted because I tried it. According to the same 
site there is a BIOS update available, but the machine shows that it already 
has it (circa 1996). According to the Enhanced IDE features, on this machine, 
I have.
Multi-sector transfer (which is set to auto)
and
32-Bit Disk I/O  (which is set as enabled)

The installation of Smoothwall Express2 creates four partitions, and uses all 
the drive, deleting whatever is on it.
hda1     /boot
hda2     swap
hda3     /var/log
hda4     /           (this one is flagged as bootable)

I had initially on the 6GB drive managed to install the Smoothwall, but 
couldn't reboot. I got an L, followed by a string of 40's. The L showed that 
the first stage of LILO was ok, and according to error codes, the 40 is a 
drive seek error. Booting up the Finnix live cd, and running fdisk -l, I got 
the partition setup as above, which corresponds with the partition setup on 
my current running Smoothwall.

>  Depending on the version of LILO, there may be an option to use LBA
>  addressing that sometimes also helps. I believe it is automatically
>  used in the latest versions, but I could be wrong. 
I don't know if I can make changes to LILO on the Smoothwall, as it's pretty 
nuch an automatic install, apart from OK'ing a few pages, and setting up the 
NIC, and entering passwords.
>  One way to see if it is a BIOS problem is to try using the same
>  drive in a more modern machine. If it boots without problems there,
>  then it is a good indication that it is a BIOS problem, or that you
>  are using 2 different settings for the hard drive. I have run into
>  problems in that past where one machine used LBA, and another used
>  the LARGE mode, or didn't support the newer modes, and you could not
>  boot from the drive in the older machine anfer installing from the
>  newer machine, even if they used the same processor. 
Well I did try the drive in another machine, just to see if it was OK, and 
Smoothwall installed on it in about 5mins, and rebooted ok, but forgot to 
boot up the drive before re-installing the Smoothwall on it. I was sort of 
losing the plot by now though, so have no idea if the old Smoothwall install 
would have booted up on the newer (circa 2003) machine.

 
>  Mikkel 
Moving on a few days, and trying various incantations on this horrible P1 
machine. The Smoothwall installed in 5mins on my other machine on this 6GB 
disk, but will not run on the P1 machine, because the harddrive limit is 2GB.

I couldn't even get the P1 machine to initialise the harddrive, and ended up 
installing Win95 from a 13 floppy set. That wouldn't run to completion, as 
disk 13 failed on installing, but at least it had installed enough so that  I 
could run smart boot manager in the floppy drive, and boot Finnix from the 
cdrom drive, but no joy on getting the Smootwall installed on this machine.

Perhaps we should just close this thread as unresolved. I've spent many hours 
getting nowhere, and extremely frustrated in the process.

Apologies for the late reply, but I've been trying allsorts of incantations to 
get this damn machine to play ball with me.

Nigel.

[Mikkel]

Nigel Henry wrote:
>  On Friday 26 October 2007 02:59, Mikkel L. Ellertson wrote:
> > I suspect that you are trying to read part of the drive that
> > the BIOS of that machine can not access. An updated BIOS may help.
> > If not, using a /boot partition at the start of the drive will help.
> > Remember, both LILO and Grub use the BIOS to access the hard drive.
>  
>  Hi Mikkel. Sorry for the delay in my reply. I've been reading, reading, and 
>  more reading about LILO. I use LILO on my Debian installs, and havn't had 
>  problems with it. 
Not a problem - lists like this are great for problems you work on
in your spare time.

>  I believe you're right in it being a BIOS problem. I've 
>  been on the site that has docs, specs, etc for this AST Bravo MS 5133 
>  machine, and it was shipped with a 1.2GB HDD, and Win95, with possibilities 
>  of a 2GB one being used (1024 cyl limit in the BIOS setup). The drive my son 
>  had Win 2000 pro on is a 6GB one (13328 cyl). Quite how he got it set up, 
>  I've no idea, but I know it booted because I tried it. 
Windows boots from the start of the partition. It probably only had
the Windows partition on it, and once Windows boots, it no longer
uses the BIOS to access the drive. (Not always true, but usually the
case.) On the other hand, there may be a BIOS extension on the MBR
that lets the BIOS work with larger drives. I remember dealing with
several versions of them in the past. Drive Manager was one of the
more common ones.

>  According to the same 
>  site there is a BIOS update available, but the machine shows that it already 
>  has it (circa 1996). According to the Enhanced IDE features, on this machine, 
>  I have.
>  Multi-sector transfer (which is set to auto)
>  and
>  32-Bit Disk I/O  (which is set as enabled)
>  
>  The installation of Smoothwall Express2 creates four partitions, and uses all 
>  the drive, deleting whatever is on it.
>  hda1     /boot
>  hda2     swap
>  hda3     /var/log
>  hda4     /           (this one is flagged as bootable)
>   
If the /boot partition is the first one, then having partition 4
marked may be the problem, depending on the BIOS. Changing this to
the first partition may let the system boot.

>  I had initially on the 6GB drive managed to install the Smoothwall,
> but 
>  couldn't reboot. I got an L, followed by a string of 40's. The L showed that 
>  the first stage of LILO was ok, and according to error codes, the 40 is a 
>  drive seek error. Booting up the Finnix live cd, and running fdisk -l, I got 
>  the partition setup as above, which corresponds with the partition setup on 
>  my current running Smoothwall.
>  
> > Depending on the version of LILO, there may be an option to use LBA
> > addressing that sometimes also helps. I believe it is automatically
> > used in the latest versions, but I could be wrong.
>  
>  I don't know if I can make changes to LILO on the Smoothwall, as it's pretty 
>  nuch an automatic install, apart from OK'ing a few pages, and setting up the 
>  NIC, and entering passwords.
> > One way to see if it is a BIOS problem is to try using the same
> > drive in a more modern machine. If it boots without problems there,
> > then it is a good indication that it is a BIOS problem, or that you
> > are using 2 different settings for the hard drive. I have run into
> > problems in that past where one machine used LBA, and another used
> > the LARGE mode, or didn't support the newer modes, and you could not
> > boot from the drive in the older machine anfer installing from the
> > newer machine, even if they used the same processor.
>  
>  Well I did try the drive in another machine, just to see if it was OK, and 
>  Smoothwall installed on it in about 5mins, and rebooted ok, but forgot to 
>  boot up the drive before re-installing the Smoothwall on it. I was sort of 
>  losing the plot by now though, so have no idea if the old Smoothwall install 
>  would have booted up on the newer (circa 2003) machine.
>   
I should have been clearer here - what I was talking about was
taking the drive, and, without making any changes to it, put it in
another machine and see if your installation would boot.
>  
>  Moving on a few days, and trying various incantations on this horrible P1 
>  machine. The Smoothwall installed in 5mins on my other machine on this 6GB 
>  disk, but will not run on the P1 machine, because the harddrive limit is 2GB.
>   
You can bet around this in Linux by telling they system that it has
a 2GB drive, and making sure all of /boot is on the part the BIOS
know about. You may have to give the true drive specs to fdisk, but
you can have the /boot, swap, and any other partitions except /boot
on the part the BIOS does not know about. I used to do this a lot in
the past with 386, 486, P1, and the AMD equivalent systems. As long
as the BIOS did not lock up when trying to boot with the large
drive, Linux was more then happy to use all of it. It was also
common to have both /boot and a windows partition in the part the
BIOS knew about.

One thing you have to be careful about is that this BIOS probably
only understands the "normal" drive geometry, so if you install on
another machine, and intend to move the drive to this machine you
have to make sure you do not use the LARGE, LBA, or AUTO settings
for the drive. Otherwise, you will bet strange results when you try
and boot. You may get as far as the LILO prompt, and error out when
loading the kernel.

>  I couldn't even get the P1 machine to initialise the harddrive,
> and ended up 
>  installing Win95 from a 13 floppy set. That wouldn't run to completion, as 
>  disk 13 failed on installing, but at least it had installed enough so that  I 
>  could run smart boot manager in the floppy drive, and boot Finnix from the 
>  cdrom drive, but no joy on getting the Smootwall installed on this machine.
>  
>  Perhaps we should just close this thread as unresolved. I've spent many hours 
>  getting nowhere, and extremely frustrated in the process.
>   
That is up to you. I can understand you being frustrated with this
machine, and not wanting to fight with it any longer.

>  Apologies for the late reply, but I've been trying allsorts of
> incantations to 
>  get this damn machine to play ball with me.
>  
>  Nigel.
>   
Again, no apologies needed. This is not the first stretched out
thread, and it will not be the last one. This is more what the list
is for then some of the long rants we have had here lately. (For
that matter, it is better then my ramblings about some of the old
CP/M machines I have played with!)

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!