Re: Concern for my data on large partition

[Space Ship Traveller]

Hello again;

> Not quite - the MSDOS MBR cannot represent offsets larger than 2TB, so
> it's not just that partitions may not exceed this size. No offset
> (beginning or ending) of a partition may exceed 2TB on an MBR-labeled
> device. I.e. it's not possible to safely take a device >2TB in size  
> and
> divide it into partitions that are 2TB or less in size.

Thanks for the clarification.

> > might want to try using GPT (use mklabel gpt).
> > - fdisk doesn't support large partitions. you should be exclusively
> > using parted at this point.
>
> GPT is the only sensible choice if you're determined to partition a
> device of this size. Be aware that it does have some caveats - in
> particular, most non-ia64 systems cannot boot from GPT volumes without
> resorting to brittle hacks.

A few other points:
	- I've had a problem where a GPT partition table wasn't recognised on  
an older kernel, but re-creating the partition (on the older machine)  
table solved the problem. This might indicate that older kernels  
aren't quite as tolerant of values as newer kernels. This shouldn't be  
a problem if your simply using one machine.
	- Older versions of parted don't work well with GPT (or even at  
all)... make sure you get the latest stable release for your platform.
	- I've had problems recently with Ubuntu - PowerPC version doesn't  
have support compiled into the kernel by default, you'll need to  
recompile the standard PowerPC distribution if you want it to work. Be  
aware that GPT is not available or supported on all platforms; this  
was a surprise to me since there is no logical reason why it shouldn't  
be included.
	- GPT support is fairly new and therefore you are likely to find  
other bugs and it isn't "well supported" when compared to standard  
msdos partition formats.

I found the tool "disktype" invaluable when solving some partition  
problems.

http://disktype.sourceforge.net/

It prints out the structure of a disk regardless of operating system  
support - this includes file system formats.

Kind regards to everyone,
Samuel