Can I change the Partition table without losing data ?

[Vahids]

I want change partition table to GUID for some test .

I have WD 500G Green Hard Disk in my laptop.
But there is a lot of data that I need.

[Roxoff]

You may be able to hack things around using tools like parted (or the pretty qtparted, et. al.) But my advice is don't do this with a live, working system. It's the sort of project that will cause you all kinds of headaches.

Either: back up your data and be prepared to re-install everything and restore your data when it breaks, or get another hard disk and try it on that. You can set the other hard disk up how you want, you could even copy your existing hard disk.

[Vahids]

You may be able to hack things around using tools like parted (or the pretty qtparted, et. al.) But my advice is don't do this with a live, working system. It's the sort of project that will cause you all kinds of headaches.

Either: back up your data and be prepared to re-install everything and restore your data when it breaks, or get another hard disk and try it on that. You can set the other hard disk up how you want, you could even copy your existing hard disk.

It's risky, I should wait to find new Hard disk. and test on that disk.

[alf55]

I want change partition table to GUID for some test .

I have WD 500G Green Hard Disk in my laptop.
But there is a lot of data that I need.

The partition tables (MBR and GTP) are not the same size and changing from a MBR to a GPT will result in data loss.

See GUID Partition Table - Wikipedia, the free encyclopedia and http://en.wikipedia.org/wiki/Master_boot_recordp.

[Rubberman]

What alf55 said. The layout is different, and you probably won't be able to assign the same sectors to the partitions.

[Vahids]

If i changed to GUID,
Can I restore Linux partition on new partition table?
Dose Linux works on GUID partition table ?

[alf55]

If your data is on a different drive, you could restore it from that drive. Changing from a MBR to GPT will not allow any of the partitions to be kept (all will be lost).

Yes, Linux can use GTP tables (at work we have drives upto 12TB with GPT). It does not make much since under 2T as MBR works fine for them but it is capped at 2TB total space access (regardless of the partitioning). GTP writes two partition tables while MBR only has one and the MBR fits into one sector which also has the startup (or the first part of the startup code) while GPT starts officially in the next sector but uses the first sector to indicate to MBR only partitioning tools (fdisk, sfdisk, cfdisk) that they are not act without asking the user. In the linux world, the "parted" command (and it's GUI wrapper) can work with either MTR or GPT formats (only one per drive).

In case you have not realized it all data on the drive will be lost when you switch partitioning types. The ONLY way to restore any data is from another drive.