NOTE- We originally tried to use the Kryo transcoder factory for its superior performance, but it kept running into problems trying to serialize a ConncurrentHashMap. Please use the JavaSerializationTranscoderFactory instead.
The important parts here are the docBase setting, it should point to wherever your XNAT webapp gets deployed to. Workdir can generally be left as is. The important part we are adding is the Manager section, which defines MemcachedBackupSessionManager as our tomcat's session manager. In the memcachedNodes setting, place the server settings for memcached nodes in the format "node_identifier:hostname:port". In this example, we only have one node, but if you have multiple memcached nodes (which generally is a good idea, in case one of them crashes), you can list them here separated by commas. For example, lets say we had two memcacheds, we could use: "memcachedNodes="n1:localhost:11211, n2:otherserver:11211, n3:otherserver:11211". The "failoverNodes" configuration parameter is optional but can be useful for specifying a backup server, for even more robustness. IMPORTANT: this configuration needs to be identical for every tomcat in your cluster.