@adm-marvellous.chimboza We don't use public IP Address for Azure VM in order to install mobility agent.
The Azure Site Recovery service contributes to your disaster recovery strategy by managing and orchestrating replication, failover, and failback of on-premises machines and Azure virtual machines (VMs). See here Set up disaster recovery for Azure VMs
Set up outbound network connectivity for VMs: For Site Recovery to work as expected, you need to modify outbound network connectivity from the VMs that you want to replicate.
Note:Site Recovery doesn't support using an authentication proxy to control network connectivity.
This is the requirement, We don't need public IP address,
For more information: You may refer to the Prerequisites and also it will allow only the mentioned IP's has per the prerequisites.
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Hope this helps! Kindly let us know if the above helps or you need further assistance on this issue.
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