Hello @Krishnamoorthi ,
Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.
It is unclear as to what you are referring to as Instance id here. In azure each virtual machine is identified with its own unique instance id. As far as we consider azure VM backups using recovery services vaults in azure, you can restore a VM from backup to an alternate location and create another VM which will be a unique instance again. This is through "create a new VM" restore option
For details on azure VM backups restore refer to the following links
https://learn.microsoft.com/en-us/azure/backup/backup-azure-arm-restore-vms
For detailed information on restore of VMs : https://learn.microsoft.com/en-us/azure/backup/about-azure-vm-restore
Hope this helps!
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