Redis Session Cache Overview

This section provides an overview of the Redis Session Cache.

The Failover Environment
The Redis session cache is most commonly used in a scenario where client requests are directed by a load balancing mechanism to two or more replicated WebSEAL servers.
The Redis Session Cache
Redis is an open source (BSD licensed), in-memory data structure store, used as a database, cache and message broker.
Failover for the Redis server
High availability in Redis is achieved through master-replica replication.
Redis Collections
The WebSEAL remote Redis session cache has the concept of 'collections' of replicated Redis servers to help with client-side partitioning of sessions.
Redis Keys
When a session is sent to the Redis server by WebSEAL up to 3 keys will be created in the Redis server to represent the session.
Redis session cache process flow
In a Redis session cache environment, the client browser sends requests to the WebSEAL server cluster, which then interacts with the Redis server for session management.
Sharing sessions across multiple DNS domains
When operating in a multi-domain environment, you must use a different mechanism to communicate the session identifier to the WebSEAL servers in the different DNS domains.
Advantages of using the Redis session cache
The Redis session cache solution has many advantages over the failover cookies solution for maintaining session state.
Restrictions when using the Redis session cache
There are a number of restrictions which apply when you are running a WebSEAL environment that utilizes a remote Redis session cache.

Parent topic: Redis Session Cache