If you want to connect to an appliance deployed in AWS Marketplace, use the instructions provided in Connecting to Existing Veeam Backup for AWS Appliances. At the Connection Type step of the wizard, select Private network and specify the private IP of the appliance.
If you want to connect to an appliance deployed using Veeam Backup & Replication, you must delete the appliance from Veeam Backup & Replication infrastructure and then add it as described in the previous paragraph. This is required because Veeam Backup & Replication deploys appliances using their public IPs.
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