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The Basics

As a Skype for Business-native application, Clarity Connect uses the same approaches to high availability (HA) and disaster recovery (DR) as Skype for Business.

High availability configurations are robust and intended to operate continuously without failure for an extended period of time by using redundant components in a single location.

Disaster recovery sites exist in a geographically separate location and enable the recovery or continuation of technological infrastructures following a major outage.

Environment

Clarity Connect depends on the capabilities provided by the Skype for Business server and can only be as highly available as the underlying Skype for Business server environment.

Keep in mind that because Clarity Connect is native to Skype for Business, all Clarity Connect functionality is routed through Skype for Business; nothing is duplicated. If Skype for Business functionality is compromised at any point, Clarity Connect will also be affected. Because of this, there is little value in deploying Clarity Connect in a highly available configuration alongside a single-site standard edition deployment on a Skype for Business server.

High Availability (Active/Active)

In a highly available (active/active) configuration, server pooling allows multiple servers with the same role to be grouped together to share load and ensure continued availability in the event of an outage. The number of servers in the trusted application pool must be at least one more than the number of servers dictated by the desired concurrent call capacity.

A secondary site dedicated to disaster recovery is recommended in addition to a primary high availability configuration.

A hardware load balancer is required to properly distribute messages sent to the pool. Web traffic for Clarity Connect must also be load-balanced.

Highly available configurations:

  • exist in a single location
  • increase normal operating capacity
  • do not require manual intervention for failover
  • require N+1 servers
  • have a potential for outages if an entire site is lost
  • may not comply with disaster recovery requirements as they are single sites

Disaster Recovery (Active/Passive)

A disaster recovery site is a second Clarity Connect deployment in a geographically separate location that has the capacity to stand alone as an independently functioning site should the original deployment become inaccessible. Servers at the disaster recovery site must mirror the application server set up at the primary site. This second site also requires a database that is replicated from the main site.

Clarity Connect supports SQL server replication and mirroring for databases in disaster recovery configurations. For the most stable experience, use a witness server to provide automatic failover when using SQL server mirroring.

Disaster recovery sites:

  • exist as a secondary and independently functioning site
  • do not compromise capacity
  • may require manual intervention for database failover
  • require the same number of servers that exist at the primary site
  • allow servers to sit idle until needed
  • require regular testing and maintenance
  • may require reconfiguration of Skype for Business endpoints