Is it possible to create a software RAID 1 with different sector sizes?

I bought a hard drive of a different model to my main drive and tried to mirrored them, but the following error message came up in Windows 7 Virtual Disk Manager:

All disks holding extends for a given volume must have the same sector size, and the sector size must be valid.

My disks have the following stats:

Main drive: SAMSUNG HD103SI, physical sector size 512b.
Mirror drive: WDC WD10EARX, physical sector size 4096b.

Running chkdsk they both report 4096 bytes in each allocation unit, which I assume is another way to say "virtual sector size".

Do the physical sector sizes have to match? Can I somehow reformat a drive to match the other? It'd be nice if I could use different drives, then I could step-wise upgrade in the future.

I was thinking that I could clone my main drive to my mirror drive and then use the main drive as a mirror instead. Would that work, or it would just be a huge waste of time?

EDIT: I noticed that I can create a mirrored volume on both drives from 2 unallocated drives. but when I create a volume first, right click it and then try the option "add mirror" it always gives the "sector size error" message to me. is this a bug? Why does add mirror" not work?

Anyway, assuming I will have to reinstall windows 7 on them, I am going to follow this guide here and well see how it goes: http://my.opera.com/Devocalypse/blog/2011/03/02/install-windows-7-on-a-dynamic-disk-pro-and-ultimate-only

EDIT: It works. Managed to install Windows on the "mirrored volume" by following the guide, however I still want to copy/clone my current "main volume" to the dynamic disk.

EDIT: Bought another identical disk this time and now the "Add Mirror" button works. I clone the data onto the new disk then boot from there then I press "Add mirror" and it works. Now I am trying to figure out why the other mirrored drive won't boot.


Solution 1:

Yes, it is possible to run RAID-1 on harddrives with different physical sector sizes.

Having said that, it might not be a good idea. If your software RAID-1 implementation writes in 512 bytes chunks then it will be inefficient and slow. This is probably not a problem since most filesystems use chunks of 4k and most stripe sizes on RAID are 64Kb or larger.

However in rare cases you could get really bad performance. Especially if you did not align the filesystem on a 4k boundary.