Help understanding Windows 10 System Disk layout, for reliable cloning


  1. Posts : 69
    Windows 10 pro, 64 bit
       #1

    Help understanding Windows 10 System Disk layout, for reliable cloning


    Shortly after porting a few major apps and data groups to my Win-10 (pro, 64 bit) machine, I wanted to make sure I could clone my hard drive. I did so successfully with a very powerful tool I'll recommend everyone have, especially since you can do most operations with the free version. Its called "Minitool Partition Wizard", and don't let the name fool you... there's nothing "mini' about it.

    Anyway, while in the process of cloning I was a bit confused at what I was seeing. My windows 10 system disk was 500gig, and starts with a sizable (about 1G) partition called "System Reserved", which has no associated drive letter or file system type. After that, the remainder of the disk is my C: drive, NTFS. My wife also has a windows 10 laptop with a similar layout, except that there is an additional backup partition.

    Now I personally don't believe in backup partitions. I always backup to a separate drive. But in any case I used the "migrate OS wizard" in that MIniTool app to make my "clone". I was curious to see whether it would even bother with the the "System Reserved" partition. Well it did, and the new HD I copied to had a very similar layout, though the new drive was bigger (1T) and the copy seemed to proportionally increase the size of each partition in a sensible way. I tested the new drive by disabling the original HD in my BIOS to make sure it could boot from the new one, and that I had a fully operational system without the original drive.

    Well all was well! So that's a sigh of relief! But still I would like to better understand the layout and requirements of this oddly formatted windows 10 system drive. Just what is the "System Reserved" partition anyway? And would there ever be a need to change anything in it? Would also be nice to know what info i need to understand, to figure out what kind of cloning software (besides my "MiniTool" ) can properly clone a windows system drive? What software should I avoid? And are there any special rules regarding adding other partitions that were never in question back in the windows 7 days?

    A lot of questions I know. I would just like to understand more of the nuts and bolts involved with this new (or new to me) disk structure. Any tutorials or recommended articles or online docs appreciated! Thanks in advance!
    Last edited by PeterPan2000; 04 Feb 2020 at 22:09. Reason: errant spelling
      My Computer


  2. Posts : 13,301
    Windows 10 Pro (x64) 21H2 19044.1526
       #2

    I personally prefer Macrium (there is a free version) for imaging and restoring a drive.
    It also has fix boot option you can have on a rescue disk in case cloning doesn't work
    properly.
    I have had many failures with cloning so its my preference to image the drive
    so I can try again if there is a failure.
    The issue in cloning is that some system files are hard to copy as they are in use
    while the image has none.
    There are a number of other cloning and imaging programs Acronis, easeus , etc
    Macrium has been the simplest and easiest for me and to date no failures.
      My Computers


  3. Posts : 18,432
    Windows 11 Pro
       #3

    The system reserved partition normally is the partition on a system using legacy BIOS (or UEFI in CSM mode) that the computer boots from. It is normally an NTFS partition marked as active on a drive with the MBR partition table type. However, 1 GB is an excessive size for a system reserved partition that only needs to contain about 50-60 MB of boot files. 100 MB is considered to be the minimum size for a system reserved partition.
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  4. Posts : 19,518
    W11+W11 Developer Insider + Linux
       #4

    Can you post a picture of your Disk Management ?
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  5. Posts : 11,247
    Windows / Linux : Arch Linux
       #5

    Hi folks

    As others have pointed out --If you CLONE a HDD it's best to simply Clone that HDD when its not being used by the system -- so if it's say the "C" or OS HDD you want to clone then use the stand alone recovery media (create from Macrium etc) to perform the Clone.

    You can delete the recovery partition with a partition manager -- again if it's the Windows "C" drive then you'll have to do it via a bootable partition manager -- GPARTED for me is as good as it gets for this type of stuff for managing partitions.

    Cheers
    jimbo
      My Computer


  6. Posts : 240
    Dual Boot Windows 11 & 10, usually latest version
       #6

    PeterPan2000 said:
    Shortly after porting a few major apps and data groups to my Win-10 (pro, 64 bit) machine, I wanted to make sure I could clone my hard drive. I did so successfully with a very powerful tool I'll recommend everyone have, especially since you can do most operations with the free version. Its called "Minitool Partition Wizard", and don't let the name fool you... there's nothing "mini' about it.
    One of my favorite disk tools.
    Now I personally don't believe in backup partitions. I always backup to a separate drive. But in any case I used the "migrate OS wizard" in that MIniTool app to make my "clone". I was curious to see whether it would even bother with the the "System Reserved" partition. Well it did, and the new HD I copied to had a very similar layout, though the new drive was bigger (1T) and the copy seemed to proportionally increase the size of each partition in a sensible way. I tested the new drive by disabling the original HD in my BIOS to make sure it could boot from the new one, and that I had a fully operational system without the original drive.
    !
    Minitool has options to expand the partitions to fill the entire drive, or to keep all partitions the same size as the original size.

    I have have had much better success cloning a disk for backup then using conventional backup programs or imaging programs (especially from Windows 7). Macrium Reflect is the first imaging program i've used that I have any confidence in. Macrium is also an excellent cloning program, if neither disk has any disk errors.
      My Computers


  7. Posts : 69
    Windows 10 pro, 64 bit
    Thread Starter
       #7

    my disk manager, since someone asked


    Help understanding Windows 10 System Disk layout, for reliable cloning-disk.jpg

    - - - Updated - - -

    I'm pretty happy with my "Minitool Partition Wizard" product, especially now that I've seen it work. To be fair, the option of cloning the system drive which is in use seems a little scary. The tool accomplishes this by completing the task on the next reboot. This is similar to the way even the old Norton Ghost used to work, and frankly I don't like it either, because it MUST put that task on the drive you're attempting to clone. Truth is, its a pretty safe process, but that's how the free version works. The paid version which I bought (pretty cheap IMHO) can use that same procedure, BUT also includes an ISO image yuou can use to burn a bootable disk version from. I like that better because as others have pointed out, it just seems safer to perform such operations on a drive that is not "in use". And I concur with some of you that a CLONED drive is a very good backup, which I too trust much more than I've ever trusted windows backups.

    But this is secondary, because my cloning process does work. I'm still somewhat curious why that reserved partition is needed and seems standard in all win-10 systems. I've got some got info from some of you, so thanks for that. I will explore more on google about this mysterious "reserved" partition. If its tied to the system BIOS as one of you suggested, then I wonder what would ever happen if my computer was fried, and I wanted to move my hard drive (or a clone) to another machine. BIOS requirements would surely be different! The computer was purchased from a computer store that sells on ebay, and they did not have a windows install disk to offer me. So while I'm glad I have the protection of cloning my system drive, I wonder if I'd be up the creek without a paddle if the computer itself failed! Just trying to plan for all contingencies. Sorry for rambling!
      My Computer


  8. Posts : 19,518
    W11+W11 Developer Insider + Linux
       #8

    Cloning is fine and dandy as long as certain conditions are met like if disk is same size or larger than initial disk and is in good, practically perfect order. Making full system backup is prevention from disk failure and is more flexible. Macrium Reflect for instance can do cloning as well as making a backup that is substantially smaller (up to 75% of initial disk used space). has ability to make own bootable rescue disk/USB, resulting backup file could be copied in several places ensuring true backup with less effort and more security.
      My Computers


  9. Posts : 920
    Windows 10 Pro
       #9

    A good starting point is the wiki pages such as Microsoft Reserved Partition - Wikipedia , there are detailed wikis for most partition layouts.
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  10. Posts : 18,432
    Windows 11 Pro
       #10

    The system reserved partition is in no way tied to a specific BIOS. You can easily do away with the system reserved partition by running:
    bcdboot C:\Windows /s C:

    Then make sure the partition containing C: drive is marked as active.
      My Computer


 

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