Independent

Active-Active Redundancy through Equal and Independent sites

Primary recorders are part of one Milestone deployment, while the Secondary recorders belong to a separate, independent Milestone deployment. This architecture features two unique databases, one at each site. The sites are not Federated. Each camera streams to both sites simultaneously.

This setup ensures redundancy for all XProtect components, including the Management Server, Event Server, SQL Server, and Recording Servers.

Independent Architecture

Pros

1. Cybersecure Design: Separate data centers with no inter-site clustered components enable independent cybersecurity policies at each. A compromise in one does not automatically compromise the other.

1. Clean Software Update Workflows: Since there are no inter-site clustered components, one site can be taken offline completely while the other site continues to serve clients. If things go wrong during an upgrade, the blast radius is contained within a single site.

2. SQL Insulation: There is no cross-site SQL clustering; therefore, SQL corruption in one site does not automatically affect the other site. RMF achieves all SQL synchronization through the Milestone API, which fails when reading from a corrupt database.

3. Cleaner user experience: Since sites are independent, camera visibility and alarm handling are straightforward. In contrast, in a Federated architecture, child site cameras are visible in the parent, resulting in the user seeing two sets of cameras in the client.

Cons

1. No Stream Level Failover in RMF: RMF does not support stream-level failover in the Milestone Smart Client. However, one can achieve this by using a PSIM, such as Prysm, that supports failover with an independent Milestone site.

2. Increased levels of redundancy require higher infrastructure costs for multi-server deployments.