Windows 2008 cannot add mirror

For the purposes of this tutorial we will be working with a system containing a GPT system disk and a new disk numbered as disks 0 and 1 respectively. The objective will be to mirror the GTP system disk on disk 1. The mirroring process will be performed from the command prompt using the diskpart tool which can be launched by opening a command prompt and typing diskpart.

In the above output, disk 0 is the system disk and disk 1 is the new disk which will be used as the mirror. Before disk 1 can be used, any existing partitions on that disk must be removed. To identify any current partitions, select this disk and list partitions as follows:. Clearly, this disk already contains a partition. If this data is required, be sure to back it up before removing any partitions. Once the backup is complete, select and delete any partitions as follows:. Since the disk no longer contains any partitions this can be now be achieved using the convert command:.

The next step is to gather information about the partitions contained on the current system disk. To do so select the system disk and list the partitions:. In order to accurately mirror the system disk these partitions also need to created on the mirror disk using the create partition command and the efi and msr options as follows:. Before this can be achieved, the partitions need to be assigned drive letters:.

Once a drive letter have been assigned, open a second command prompt window to format the EFI partition and copy the system file. Note that it may be necessary to launch the command prompt with elevated privileges. To do this, locate the command prompt in the Start menu, right click on it and select Run as Administrator. With the disk populated with the mandatory partitions, both the disks must be converted to dynamic disks using the convert command:.

After exiting from diskpart it will be necessary to reboot the system possibly twice for the conversion of the system disk to take effect. Once the disks are converted to dynamic disks the final stage in the process is to add disk 1 as the mirror for the system disk. Once again start up diskpart and execute the following commands:. This will initiate the mirroring process which may take some time depending on the size of the system volume as Windows Server carries out the resynching process.

Read this one and make sure you understand what its doing. If your second disk is blank, there wont be a operating system on there anyway. If you are dual booting on your main OS drive, you may need to check if that will be effected. Now to actually create the mirror. In this example, I will be mirroring C: drive. You will be asked where you would like to set up the destination for the mirror. The two drives will now sync, and mirror everything from the source partition, to the second drive.

It should start to show the progress of the re-sync as a percentage as shown below. This process may take awhile. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

If you are trying to use Disk Management in order to create a Mirror array with your OS drive it won't let you as all drives that are part of the future array will be swapped from basic to dynamic and formatted.

Since you have your OS and system partitions on that drive the system won't allow you to format it. What are you trying to achieve? If you want a solid backup I would recommend using an external drive to keep copies of your data offsite instead of relying on a mirrored array.

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