@Cloud_Geek_82 Apologies for the delayed response!
Configuration server: Connects to Server Migration and coordinates replication.
Process server: Handles data replication. The process server receives server data, compresses and encrypts it, and sends to Azure.
Master target server
The master target server handles replication data during failback from Azure.
By default, the master target server is installed on the configuration server.
For large deployments, you can add an additional, separate master target server for failback.
Reference doc: https://learn.microsoft.com/en-us/azure/migrate/agent-based-migration-architecture
Also, is it normal that test migration machine doesn't have a public IP address?
It is normal!
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