Sentinel is a complex multi-tier application that depends upon and provides a wide variety of services. Additionally, it integrates with multiple external third-party systems for data collection, data sharing, and incident remediation. Most HA solutions allow implementors to declare dependencies between the services that should be highly available, but this only applies to services running on the cluster itself. Systems external to Sentinel such as event sources must be configured separately to be as available as required by the organization, and must also be configured to properly handle situations where Sentinel is unavailable for some period of time such as a failover event. If access rights are tightly restricted, for example if authenticated sessions are used to send and/or receive data between the third-party system and Sentinel, the third-party system must be configured to accept sessions from or initiate sessions to any cluster node (Sentinel should be configured with a virtual IP address for this purpose).