Milestone XProtect clustered with single clustered OnGuard
When server clusters are used for redundancy, the XProtect OnGuard Integration Service requires a separate Integration Server - distributed from both the XProtect and OnGuard server. Below is the suggested architecture if both XProtect and OnGuard use server clusters:

Important
Before configuring XProtect Access with OnGuard on a system that is using clustered XProtect Management Server Failover which includes a clustered XProtect Event Server, it is required to add all of the clustered Event Server nodes to the Registered Services within XProtect. Please refer to KB 33314 for more details on using XProtect Access with clustering.