After system didaster how to prepare / save most important data ?

[Nils Kassube]

Karl Larsen wrote:
> SYNass IT Ubuntu / Linux wrote:
> > Now I prepare for extracting the most important data and appreciate
> > your hints und suggestions to get this done best and safest to
> > do a new system setup from scratch !!!
> >
> > My plans and intentions:
> > 1st: Save /home completely to a USB stick or external USB HDD !
>
>     You can do this but a USB stick will not last as long as a Hard
> Drive as a rule. 

So true. I had one that only worked for about 3 months. If available I 
would also prefer a hard disk.

> I suggest you just use another partition on your Hard 
> Drive for /home. Load it with /etc/fstab and you forget it is separate.

If the drive was healthy, that would be more or less OK, but it seems as 
if the drive is failing. Therefore it would not help to save the 
important data on the same drive.

I would just copy the entire /home directory to the external drive. To do 
that, mount a partition of the external drive to /mnt. Then use the 
command:

sudo cp -a /home /mnt

Of course the partition must be big enough for the data and it should be 
an ext3 partition. If there is only a FAT partition you may have a 
problem because you can't keep the permissions. And you can't safely use 
tar because of the file size limit of 4GB. OTOH, if compressing the tar 
file with bzip2 would reduce the size below 4GB it should work with the 
command

sudo tar cfj /mnt/home.tar.bz2 /home

with the external disk mounted at /mnt again.

> > After having all important data extracted ...
> > ... how can I verify to have good backups / saves ??

With the cp option above you could use

sudo diff -r /home /mnt/home

and there should be no output. With the tar option above it would be

tar tfj /mnt/home.tar.bz2

where every file is displayed, but there should be no error message at the 
end.

> > Recently her in the forum was a discussion about problems with hda /
> > sda while upgrading from Ubuntu 7.10 to 8.04 ! How comes 

That problem is due to 2 different parts of the kernel which can be used 
for accessing hard disks. One part will give you hda devices, the othwer 
will give you sda devices.

> > and how to 
> > overcome ??

Don't use device names, use UUIDs or labels instead.


Nils