Active Directory Replication
Active Directory replication failed because the RPC server is unavailable
The replication generated an error (1722): The RPC server is unavailable.
Active Directory replication could not connect from one domain controller to another over RPC, so the replication attempt failed with error 1722.
Observed message
The replication generated an error (1722): The RPC server is unavailable.
Why it happens
- DNS, routing, or network connectivity between domain controllers is broken.
- A firewall or security device is blocking the required Active Directory RPC ports.
- The source domain controller or supporting service is unavailable or unhealthy.
How to fix it
- Verify name resolution and basic network connectivity between the source and destination domain controllers.
- Check RPC port availability and any firewall or network security controls in the path.
- Review DCDIAG, REPADMIN, and directory service event logs to pinpoint the failing layer.
