Create Degraded RAID 1 in Windows 7

Question

Question is simple. Can one create a degraded RAID 1 in Windows 7?

In other words specific to a hypothetical situation, can I have a backup drive with backup data on it, then buy a second backup drive later and put the two in drives into a RAID 1 while always maintaining a copy of the data?

I know this can be done in Linux via creating a degraded array, copying the data to degraded array, deleting the data from lone drive, then adding lone drive to array; but I am looking at backing up to a single drive at first located in a workstation under Windows 7, then adding a drive to it in the near future.

Answer 1

You are looking for the use of dynamic disks. If you have a dynamic disk volume, you can create a mirror to another dynamic disk with enough free space at any time. It does not need to be pre-initialized for RAID. You can also mirror across more than 2 disks.

Once the mirror is created can then "break" the volume, creating copies of the mirror that are no longer linked. This can be useful for a boot drive if you want to make substantial changes, such as an operating system upgrade. In case of a failure, you can just boot from the other volume by adding a second entry to the boot manager.

You can also have a mix of dynamic volumes on a disk, such as mirrored, striped, RAID5, and regular. Here is an example of my old server with 4 disks and 5 volumes in different modes.

If you convert a disk to dynamic mode, it may be more difficult for 3rd party tools such as backup programs and disk repair utilities to access the drive. Converting back to basic mode without wiping the partition table cannot be done without use of a 3rd party tool.