Currently JBoss doesn't install JvmRouteValve for non session
replication setup. However, it's still useful in the following
scenario:

• 1 Apache HTTPD frontend and 2 JBoss AS instances without session replication, sticky session enabled
• A request goes JBoss node AAA (JSESSIONID=xxx.AAA)
• The node AAA crashed
• The request goes node BBB, lost session, recreate another, JSESSIONID won't be changed
• The node AAA recovered
• The request comes back to the node AAA, lost session again

Enabling JvmRouteValve can prevent last failure.