• Did you read this. It seems you have to jump through quite a few hoops if you want work with GPT mirrors.

    That helped.   That link seems to be for Server 2003, but piggy-backing off your search terms I found this: Doc

    This MS doc is for Server 2012, but the instructions seem to hold for Server 2016 (with very minor changes)
    I ran through the entire process, I didn't get any errors, but I didn't get it to work either.   So.. I'm going to have to try it again to make sure I didn't miss anything.

    BUT.... this is some &*^%$$%^!!!
    That's like 100x more work than the MBR method (turning those steps into a batch script is no picnic either.)
    PLUS : There is this gem right at the beginning:

    Windows does not automatically service the contents of the secondary system partition. If you install any operating system updates or service packs, be sure to manually update the secondary system partition (the mirror) with the same updates. To do this, be sure to follow Step 3 of the “Clone the system partition” procedure, where you use the Robocopy.exe command to copy the contents of the primary system partition to the secondary system partition.

    So on top of everything else you need to manually mirror one of the 3 partitions!
    This has apparently been the method since Server 2003 and the advent of GPT.
    Thanks Microsoft!    .... never occurred to you to maybe build a tool to address this?

    Let me change my question:
    Is this the best I can hope for?  Is there a third-party tool I should know about?    Is there maybe a "Virtual RAID controller" in Hyper-V that I don't know about?


  • Did you convert an old VHD to VHDX?

    No, I'm performing fresh installs each time, 2016 is pretty quick when it comes to the installation

    What happens if you select “Generation 2”? Any error messages?

    The above steps don't work if you build a GEN2 VM.
    Your VM will have UEFI firmware and a GPT boot disk.

    If you look at the partition table, you'll see 3 partitions.   Even if you add a second disc and initialize it as GPT..... the above method falls apart, because the first TWO partitions do not offer the Add Mirror option when you right click on them:



  • Today’s quest:
    Create a Server 2016 VM which uses software RAID1 while using UEFI & GPT boot disk

    Below is a working example of Server 2016 software RAID1 when using BIOS & MBR boot disk:
    This example was created on a Server 2016 Host.

    The result is exactly what I wanted:

    -          A RAID1 protected boot disc       (either disk can fail, and VM continues to run/boot)
    -          Managed purely using Windows

    But my example uses older standards:

    -          Generation 1 VM
    -          BIOS
    -          MBR


    We all know that the current standard is:

    -          Generation 2 VM
    -          UEFI
    -          GPT


    My Question:
    Is there a way to achieve the results I have shown below using the above, newer standards?
    Or did Microsoft somehow remove this capability in the name of progress?


    How I create a working Server 2016 VM which uses software RAID1 while using BIOS & MBR boot disk:

    The main trick is to create a “Generation 1” VM.  This will result in a VM using BIOS & MBR.

    When it comes to the drive partitioning, I did not create any manual partitions, just selected the whole drive.

    We get a VM with the following partitions on an MBR disk


    To configure RAID1, I add a second disk, and initialize it as MBR


    I then right-click on each partition, select Add Mirror, selecting Disk 1 as the target.

    add mirror target

    When done it looks as follows:


    When I reboot the VM, I get the following boot menu.

    boot menu

    That is all I wish to achieve…but using a Gen 2 VM.
    I have not found a solution on my own, so I'm checking if anyone knows a recipe that works.

  • Hi,

    In my current network, I’m running slightly older OS’s:

    Windows Server 2012 R2
    Windows 8.1 pro

    Some Background information:

    A while back I configured our office Wifi to use windows Domain credentials.

    The access points perform radius authentication, referencing a DC
    The DC has the access points configured as Radius Clients in NPS.

    That works as intended.  When a user clicks on the SSID of our corp wifi, they are not asked for one shared password, but for a username & password.  If they enter valid domain credentials, they gain access.

    Mixing of credentials:
    Somewhere on the Win 8.1 client there was a setting that said: “Pass the Windows credentials to Wifi”.    So:  You are already logged onto Windows with your domain account, you do not need to re-enter those same credentials to get on the corp-Wifi.

    BUT… I don’t think you can share credentials going the other way.  i.e.: “I logged into corp-Wifi successfully, now give those credentials to Windows”.   On several occasions I have actually logged into Wifi with one set of credentials, then logged into Win 8.1 with a different set of credentials.


    The Problem:

    • A user is out of the office for a week
    • their domain password expires while they are out of the office.
    • They come back to the office
    • When they open their laptop, they enter their expired password.

    At this point the laptop accepts the expired password as “cached credentials”.
    (since the password is expired, the laptop could not automatically connect to corp-Wifi)

    • User unlocks their laptop with their expired password.
      (they do not even know that the password is expired)
    • User figures out they are offline, tries to connect to corp-Wifi

    In win 8.1 the built in Wifi UI (that purple stripe on the right) has elements for dealing with expired Radius passwords.

    • The Wifi UI will present fields allowing the user to change their password.
    • User changes their domain password using this UI.
    • User gains access to corp-Wifi

    Now the user tries to print on a network printer, and it doesn’t work!
    Why?   Because while they have successfully updated their domain password, and are connected to the corporate network, they are still logged onto Windows with their old/expired password.

    At this point the user gives up and calls tech support.
    The correct remedy at this point is:

    • Logoff
    • Before logging in, connect to corp-Wifi (with the new domain password)
    • Login to Windows with the new domain password.

    My Question:
    How can I provide a more straight-forward user experience?
    The above scenario happens weekly, and traps the user each and every time.
    What can I change to avoid this pitfall?


  • Norman became a registered member 3 years, 6 months ago

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