cfdisk crashes system

[sergioroa]

Hi

I am trying to install Knoppix 3.3 on the HDD. I have done it several times in other PCs, but I have now the following problem:

Previously I had SuSE 7.3 with reiserfs and Windows 98. When I tried to install Knoppix, I received the following message from cfdisk:

"No partition table or unknown signature on partition table"

That was strange, because SuSE was detecting all partitions, but Knoppix didn't. Then I ran Windows's fdisk, erased all partitions and reinstalled Windows. Afterwards, I tried to install Knoppix, obtaining the same error message. I also tried with Linux's fdisk. Then, I decided to use cfdisk to create all partitions. But when I try to write the partition table the system crashes and no operation is performed, although the HDD Led keep turned on.

Thanks for your help!

[mzilikazi]

When you muck about with the partition table like that and do several formats w/ different file systems the hard drive tends to get a little wonky. Sounds like it's time to wipe that drive clean! Boot Knoppix and get root:

cat /dev/zero > /dev/hda

Now let me say that you absolutely do NOT want to do this on the wrong drive. Sit back for a while and let it write zeros to the entire drive. It will finish w/ an 'out of diskspace' error. This will take a long, long, long (as in many hours!) time especially on a large drive.

[sergioroa]

cat /dev/zero > /dev/hda

The system crashes when using this command. Is it normal? The command seems to do nothing, although the HDD led is still turned on.

[sergioroa]

Well, I have done some other things. I have used Gentoo LiveCD and I could finally use the command:
cat /dev/zero > /dev/hda
properly, until the error mentioned above by mzilikazi appeared. Then, I executed the fdisk utility and created all partitions succesfully. Then, I started the Knoppix CD and, again, the cfdisk and fdisk utilities don't show any partition!. In particular, fdisk behaves differently than the Gentoo's fdisk. After loading the utility, in Knoppix is shown the following message:

fdisk /dev/hda
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable

At this time, no partition is shown by the fdisk utility in Knoppix. It seems to be a bug in Knoppix partition utilities, isn't it? Should I download the last Knoppix?

Thanks in advance.

[user unknown]

while mzilikazi often gives good advices, this one isn't.

sergioroa started experiments after the patition-table wasn't found.

And doing several formats with different filesystems is what fdisk was made for.
And it works well in most cases.

Perhaps revisiting the bios-settings for the drive can help - writing 0s to /dev/something, when the partitiontable is broken is ...

sergioroa: Did you write the partitions with 'w' when using fdisk?
Don't guess fast about bugs! These guesses are wrong in 99% of the cases.

[mzilikazi]

fdisk /dev/hda
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable

At this time, no partition is shown by the fdisk utility in Knoppix. It seems to be a bug in Knoppix partition utilities, isn't it? Should I download the last Knoppix?

Thanks in advance.

After creating the partitions did you 'write' the partition table to disc? Fdisk says there is no partition table. cfdisk will ask if you would like to start with an empty table. You must be sure to [write] the partition table to disc or it will not be seen.

[mzilikazi]

while mzilikazi often gives good advices, this one isn't.

sergioroa started experiments after the patition-table wasn't found.

And doing several formats with different filesystems is what fdisk was made for.
And it works well in most cases.

Yes but he used both DOS fdisk, Linux fdisk, M$ file systems, Linux filesystems and several partition tables. There is no harm done when zeroing a drive so I fail to see how this is 'bad advice'

True the problem may lie elsewhere but again, there was no harm done to the drive by zeroing it.

[user unknown]

Your advice isn't to keep different filesystems - i.e. windows and linux - allways on different physical drives?
I had ntfs, vfat, linux, linux-swap partitions on the same drive.
And ext2 and reiserfs filesystems on the linux-partitions.

Again - what's the problem with different filesystems?

And I often used different partition-tools - made the linux-partitions with a linux-tool and windows-partitions with their tool. (Today only with the linux tool).
But it shouldn't be a problem too.

Doing no harm is a bad excuse.
You could as well give advice to reboot the system 9 times.
Will do no harm too.

But it will cost time, and give a wrong impression of what is happening/ should be happening/ might be the cause of the error.

And I never wipe a drive clean, before repartitioning.
Because it's not needed.
It's senseless.

[mzilikazi]

Your advice isn't to keep different filesystems - i.e. windows and linux - allways on different physical drives?

That's not at all what I'm suggesting. I say that when you make multiple partition table changes and multiple formats with different tools you can casue problems that can only be fixed by starting with a clean drive.

Doing no harm is a bad excuse.
You could as well give advice to reboot the system 9 times.
Will do no harm too.

But it will cost time, and give a wrong impression of what is happening/ should be happening/ might be the cause of the error.

On the contrary, we have just eliminated the first potential problem. Now we know that we have started w/ a clean drive.

And I never wipe a drive clean, before repartitioning.
Because it's not needed.
It's senseless.

Well I install an OS at least 3 times a week (no not on the same box). Trust me friend sometimes it's the only way. Also if it were not necessary to wipe a drive from time to time then why do such tools exist? Commercially even! I see you agree on using windows tools for windows partitions.

If you believe that reformatting a partition wipes away everything that was previously on that partition then you are sadly mistaken because it does not.

[sergioroa]

After creating the partitions did you 'write' the partition table to disc? Fdisk says there is no partition table. cfdisk will ask if you would like to start with an empty table. You must be sure to [write] the partition table to disc or it will not be seen.

Of course! In fact, when I try to write the partition table using Knoppix, the system crashes. When I write the partition table using Gentoo, all goes well. I restart the computer using Gentoo and I see the partitions. Then, I restart the PC using Knoppix and I don't see anything.