🚀 go-pugleaf

Adam Eberbach wrote:
> 
> I have accidentally repartitioned a hard disk using fdisk and if it's
> possible I have to reverse the actions.

Adam,
fdisk just changes the partition table. 'deleting' a partition
just removes it from the table.  I have 'detete'd and replaced a
partition before, without any dammage to the data in it.
As long as you didnt reformat it, or create a new filesystem, the
data is still there.
   Do you know where and how big the lost partiton was? It may
take some trial and error, unless you can search the raw disk
for the partition header.

I had to lose a lot of data before i got a decent backup system.
I hope you are more lucky.

-- 
Mike Holland <mike@golden.wattle.id.au>            Perth, Australia.
Quotes are a burden to others, .signatures are a prison for one's self.
---
PGP KeyID 8B3D0765. f'print= 30 07 BF 6C 9B 45 E8 C8  EA 30 4F 01 DC A2
91 88

[Posted and mailed]

In article <frobozz-2505971859100001@slbri2p64.ozemail.com.au>,
	frobozz@ozemail.com.au (Adam Eberbach) writes:
> I have accidentally repartitioned a hard disk using fdisk and if it's
> possible I have to reverse the actions. 
> 
The trick is going to be figuring out where the old partitions started and
stopped.  If you know that, you can use *Linux* fdisk to reverse the
actions and put it back.

I had a virus eat my partition table once.  Since I didn't know much about
viruses, and since I have a record of my partition layout, I did as I 
suggested and was back up.

If you don't know where the partition started and stopped, you are going to
need to look for the parition headers.  I don't remember what they look
like.  What I'd do, is get a different hard disk and partition it.  Then
look to see what the headers look like.

Note: when you think you have properly marked a Linux file system, use
fsck -n (no updates) to see if you really have.  This implies that you have
a working Linux system loaded to another drive on the computer (or have
a rescue floppy with fsck).
-- 
Hugh McCurdy

frobozz@ozemail.com.au (Adam Eberbach) writes:

> I have accidentally repartitioned a hard disk using fdisk and if it's
> possible I have to reverse the actions. 
> 
> The disk was partitioned as a primary partition with a logical DOS
> partition on the extended partition. I was trying to repartition a
> separate drive, connected as master of the primary IDE interface, CDROM on
> secondary. The disk which was wrongly partitioned was connected as master
> of the secondary interface. I don't think I was wrong in thinking that I
> wanted to partition /dev/hdc.
> 
> Sequence of events:
> Boot RedHat 4 boot & supp disks. Get to disk partitioning stage, enter
> fdisk, target /dev/hdc. Delete partitions 1,2 and 5 from disk. Think at
> the time "strange...thought there was only one?" Create one large
> partition over the whole disk, set file type to 6 (MSDOS > 32M). Reboot to
> DOS, notice a drive missing, panic!
<snip>

Partitioning can be reversed.  I have done it myself a few years ago
using the disk editor from the Norton Utilities.

You need to understand at least the basics of how a HD is layed out,
e.g. MBR, primary and secondary partition tables, partition headers.
Or get help from somone who understands this.  Expect to spend at
least half a day on this, more likely 1 to 2 days - if you cannot
afford to make even a single mistake.

Don't blindly trust automatic disk repair programs - they sometimes
can leave your disk so messed up that recovery becomes impossible.

-- 
Manfred Bartz <mbartz@werple.net.au>
  --- LINUX, live free or die ---

frobozz@ozemail.com.au (Adam Eberbach) writes:
> I have accidentally repartitioned a hard disk using fdisk and if it's
> possible I have to reverse the actions. 
> 
> The disk was partitioned as a primary partition with a logical DOS
> partition on the extended partition. I was trying to repartition a
> separate drive, connected as master of the primary IDE interface, CDROM on
> secondary. The disk which was wrongly partitioned was connected as master
> of the secondary interface. I don't think I was wrong in thinking that I
> wanted to partition /dev/hdc.
> 
> Sequence of events:
> Boot RedHat 4 boot & supp disks. Get to disk partitioning stage, enter
> fdisk, target /dev/hdc. Delete partitions 1,2 and 5 from disk. Think at
> the time "strange...thought there was only one?" Create one large
> partition over the whole disk, set file type to 6 (MSDOS > 32M). Reboot to
> DOS, notice a drive missing, panic!
> 

if you remember _exactly_ the partition-data, you could do this:

 Boot RedHat 4 boot & supp disks. Go to disk partitioning stage, enter
 fdisk, target /dev/hdc. Create partitions 1,2 and 5 with the old data and
 write it to disk.

Note:
This works only if after exiting the wrong fdisk YOU DIDN'T WROTE ANYTHING
TO /dev/hdc
No warranty...

-- 
Jan Tellkamp
Flensburg, 26. Mai 1997


Old programmers never die.
They just branch to another adress.

Per the FCA, this email address may not be added to 
any commercial mail list
(Note: bogus e-mail address - remove the leading x)

frobozz@ozemail.com.au (Adam Eberbach) writes:

> I have accidentally repartitioned a hard disk using fdisk and if it's
> possible I have to reverse the actions. 
> 
> The disk was partitioned as a primary partition with a logical DOS
> partition on the extended partition. I was trying to repartition a
> separate drive, connected as master of the primary IDE interface, CDROM on
> secondary. The disk which was wrongly partitioned was connected as master
> of the secondary interface. I don't think I was wrong in thinking that I
> wanted to partition /dev/hdc.
> 
> Sequence of events:
> Boot RedHat 4 boot & supp disks. Get to disk partitioning stage, enter
> fdisk, target /dev/hdc. Delete partitions 1,2 and 5 from disk. Think at
> the time "strange...thought there was only one?" Create one large
> partition over the whole disk, set file type to 6 (MSDOS > 32M). Reboot to
> DOS, notice a drive missing, panic!
<snip>

Partitioning can be reversed.  I have done it myself a few years ago
using the disk editor from the Norton Utilities.

You need to understand at least the basics of how a HD is layed out,
e.g. MBR, primary and secondary partition tables, partition headers.
Or get help from somone who understands this.  Expect to spend at
least half a day on this, more likely 1 to 2 days - if you cannot
afford to make even a single mistake.

Don't blindly trust automatic disk repair programs - they sometimes
can leave your disk so messed up that recovery becomes impossible.

-- 
Manfred Bartz <mbartz@werple.net.au>
  --- LINUX, live free or die ---

It's 25 May 97  21:30,
We'll return to news@golden.wattle.id.au and All's
discussion of Please help with fdisk DISASTER!

 ne> Do you know where and how big the lost partiton was? It may
 ne> take some trial and error, unless you can search the raw disk
 ne> for the partition header.

This is the key. :-)

 ne> I had to lose a lot of data before i got a decent backup system.
 ne> I hope you are more lucky.

Join the club!  I've just made up a backup CD which contains the
important nitty gritty of the systems here, just in case disaster
strikes.... AGAIN!  Last time around involved expensive repairs (and the
lucky fact that I already had a partial backup). :-)  Now I have a
complete set to start from, so I can put off HDD repairs until I aquire
the necessary bits, and load the backups onto a new disk. :-)

... Chain Tagline. Now stolen [267] times. Add 1 as stolen.
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| info@freeway.DIALix.oz.au, to receive a copy of the FAQ.

In article <5man9d$1c6@sjx-ixn10.ix.netcom.com>,
Hugh McCurdy <hmccurdy@ix.netcom.com> wrote:
>[Posted and mailed]
>
>In article <frobozz-2505971859100001@slbri2p64.ozemail.com.au>,
>	frobozz@ozemail.com.au (Adam Eberbach) writes:
>> I have accidentally repartitioned a hard disk using fdisk and if it's
>> possible I have to reverse the actions. 
>> 
>The trick is going to be figuring out where the old partitions started and
>stopped.  If you know that, you can use *Linux* fdisk to reverse the
>actions and put it back.
>
>I had a virus eat my partition table once.  Since I didn't know much about
>viruses, and since I have a record of my partition layout, I did as I 
>suggested and was back up.
>
>If you don't know where the partition started and stopped, you are going to
>need to look for the parition headers.  I don't remember what they look
>like.  What I'd do, is get a different hard disk and partition it.  Then
>look to see what the headers look like.
>
>Note: when you think you have properly marked a Linux file system, use
>fsck -n (no updates) to see if you really have.  This implies that you have
>a working Linux system loaded to another drive on the computer (or have
>a rescue floppy with fsck).
>-- 
>Hugh McCurdy

I had an interesting adventure with Solaris 2.5.1. The hardware:
PPro 180
64M mem
3.1g EIDE disk
Diamond 3d 2000, 2m video card


I had initially partitioned the disk into 3 separate 1 gig partitions:
two primaries and 1 extended.  The system already had NT on the first
1gig, and linux on the 3rd gig.  I needed to port some software to
Solaris 2.5.1 and proceeded to put it on the 2nd 1gig partition. It turns
out that the out-of-the-box Solaris 2.5.1 for x86 did not 1) handle a
3.1g ide disk properly or 2) support the Diamond 3d 2000 card. I had
to download 8 floppies worth of driver updates. After applying all the
updates I proceeded to run the Solaris equivalent of fdisk to partition
the disk. Being a paranoid sort, I thought it would be a good idea to
boot linux and run linux fdisk to make sure that the Solaris partition
program didn't mess anything up.  Good thing I did that! Solaris
had messed up the partition info (made the Solaris partition overlap
Linux by a little). Fortunately I had written down all the partition
info before I started (and the Linux extended partition had about 6
logical partitions within it). Using fdisk I was able to restore the
linux partition info. I then went back and install Solaris and had no
further problems. So, to reiterate what someone else said: if all you
did was repartition your disk, all the original data is still there --
just repartition to your original configuration.

--peter gross
pag@probita.com