This article documents configuring an environment so Veeam Backup & Replication Object Repository will use Google Cloud Private Access to connect to a GCS bucket instead of the public IPs.
Connectivity from on-premises to private access can be accomplished via Cloud VPN or Direct/Partner Interconnects to Google Cloud, and Private Access enabled on the VPC Subnet.
Note: Backup repository servers located in GCE need to be on a VPC Subnet where Private Access is enabled.
Preparing the Environment (link)
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