Migrating from reiserfs to ext3

[youshi10 at u.washington.edu]

On Thu, 30 Aug 2007, Adam J Richardson wrote:

> Konrad Scorciapino wrote:
>> Anybody ever tried something like that? Are there utilities that could help
>> out, or dangers I need to avoid?
>
> Hi Konrad.
>
> I tried that once. I managed to destroy a disk and lose almost 30GB of data. I 
> still cry over that one. Mind you, I was using Windows, back in the days of 
> FAT. I knew even less than I do now.
>
> It'd be much easier and safer to copy everything to another disk and then erase 
> that partition. You'd lose less hair, sleep and sanity. If you do go ahead with 
> this salami slice procedure, halfway through it you'll be cursing the day you 
> were born. You'll have to concentrate so as not to overwrite the wrong 
> partition. Get it wrong once and you've lost your data or one of your OSes. 
> It's boring, tedious and mind numbingly dull, which increases the odds of a 
> mistake. Really, I'd bite the bullet and buy a nice shiny new backup HDD. I'd 
> do it to avoid the tedium alone.
>
> 180GB... a 200GB HDD shouldn't be that expensive, although I grant it's been a 
> while since I bought a HDD. Perhaps a geek friend has a spare HDD you can 
> borrow?
>
> HtH,
> Adam J Richardson

Gnu's fdisk command views reiserfs and ext3 partitions as ext3 partitions, but don't believe that information. reiserfs and ext3 are completely different systems, even though their superblock info looks the same.

The only way to properly move from one filesystem to another, is to:

1. Backup all the files on another medium.
2. Wipe the disk clean.
3. Reformat with the new FS of choice.

<ot>
There's no real way around this for FS'es, with the exception of NTFS and vfat/fat32/msdosfs, where Partition Magic can come to your rescue. All Partition Magic does though is shrink M$ partitions on the fly (before boot) and shuffles around clusters of data. This of course assumes that you have enough space to begin with ;).
</ot>

Cheers,
-Garrett