Copying and expanding partitions

Question

I currently have the following setup:

1. 2TB HDD /dev/sda:

   • /dev/sda1: (NTFS) Windows 7 Boot Partition: 100GB

2. 1TB HDD /dev/sdb:

   • /dev/sdb1: (EXT4) Linux General/Backup Partition - 1TB

3. 256GB SSD /dev/sdc:

   • /dev/sdc1: (FAT) Windows 7 Loader Partition - 100MB
   • /dev/sdc5: (EXT4) Main Linux Boot Partition - 255.9GB

Here's what I'm going to do. /dev/sdc, the SSD, will be combined with other SSDs in a RAID-0 configuration. /dev/sda will be combined with other drives into a RAID-6 configuration. /dev/sdb will most likely become entirely NTFS for Windows space.

Is there a way that I can copy /dev/sda1, /dev/sdc1, and /dev/sdc5 to files on a filesystem in order to then create partitions out of them? After configuring the arrays and setting up GPT on each virtual drive, is there a utility I can use to create the partitions from backup files?

Better yet, is there a way to compress down these partitions on the FS so that empty blocks are not copied so I only have to store what's actually there?

Essentially, what I'd like to do is to make an optimized backup of these partitions, then install them where they need to go, then expand them as need be to fill the disks. I know how to expand partitions, but is there a relatively easy way to back them up and flash them back?

Answer 1

I may only suggest a solution for ext4 file system: just use dump or dumpe2fs for creating a backup, then restore utility for decompressing it. You may create (compressed) backup files and restore them on a newly created file system. All empty blocks will not be included in backup, while all other data will be kept as it is. dumpe2fs is better then tar since it also keep information about inode and other metadata.

Answer 2

With the exceptions of moving partitions to other devices and partition numbers, Clonezilla is an awesome tool for creating compressed backups of a lot of different filesystem types. There's nothing quite like being able to restore to exactly where you left off in every way.