Hello @Nikhil Goyal Thank you for contacting us through Microsoft Q&A platform. Happy to help!
When you restore the backup of an OS disk in Azure, it will restore the entire disk including the operating system, applications installed, and any other data that was on the disk at the time of the backup. However, it's important to note that restoring the OS disk backup will not restore any cluster configuration that may have been in place.
If you need to restore a cluster configuration, you will need to do so separately. Additionally, if you have any data disks attached to the VM, you will need to restore those separately as well.
It's also worth noting that when you restore an OS disk backup, you will need to create a new VM to attach the restored disk to. You cannot simply attach the restored disk to the original VM.
I hope this helps! Feel free to ping if you have any further questions.
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