...
BugZero found this defect 4875 days ago.
A Backup or Replication job utilizing Application-Aware Processing fails with the error: RPC error:The RPC server is unavailable. Code: 1722
Possible causes include, organized from most common to rarest: The ports that Veeam Backup & Replication is attempting to use are blocked by a firewall. Antivirus or Antimalware software may attempt to interact with the VeeamVSSSupport service executable. The VeeamVSSSupport service is stuck on the Guest OS Dynamic port allocation needs to be configured.
Firewall / Ports A complete list of used ports can be found here: https://helpcenter.veeam.com/docs/backup/vsphere/used_ports.html#ms_servers When Veeam Backup & Replication connects to a VM, it creates firewall exclusions for the ports and processes it uses. Veeam Backup & Replication, however, cannot add firewall exclusions to hardware or third-party software firewalls. The Dynamic RPC ports assigned to the temporary guest agents are the most common ports that cause this issue when using Application-Aware Processing. Dynamic RPC port range: 49152 - 65535 Note: The NIC’s Network Location being set to Public mode will also cause this, as Public mode sets the firewall to its strictest settings.