Azure Retain Private IP Ranges

The "Retain private IP range" toggle is enabled by default. This flag allows for the supported resources to retain the private IP address.

The following matrix defines the behavior of the private IP allocation on the recovered resources.

Retain private IP range	VM	VMSS	Load balancer	Application Gateway	Private Endpoint
Enabled	Private IP retained	Private IP not retained	Private IP retained	Private IP retained	Private IP retained
Disabled	Private IP not retained	Private IP not retained	Private IP not retained	Private IP not retained	Private IP not retained

The Retain Private IP ranges toggle can be used along with the " Enable VNet mapping " option.

Case 1:

When the CIDR ranges of the virtual network and its subnet are an exact match we can leave the "Retain private IP ranges" as enabled, as the recovery will not impacted due to the same IP ranges.

Case 2:

When the CIDR ranges of the virtual network and its subnet are not an exact match then it is recommended to disable the "Retain private IP ranges".

When "Retain private IP ranges" is disabled the recovered resources IP will be dynamically allocated based on the CIRD of the virtual network selected in Vnet mapping.

When "Retain private IP ranges" is enabled the resource will look for the same private IP ranges in the recovery virtual network which may not be available and will cause the recovery to fail.

It is always recommended to disable "Retain private IP ranges" when " Enable VNet mapping " is enabled with Vnet and subnet with different CIDR ranges.