具有自动缩放属性的EC2实例上tomcat的Memcahed会话管理器

Question

Assuming that I have two tomcats running on two EC2 instances and I have two memcached nodes running two different EC2 instances. And the EC2 instances on which tomcats are running, are behind one load balancer. I have enabled sticky session functionality. And assuming that I have implemented auto-scaling property. So whenever a new instance comes up with tomcat installed, do I need to change its tomcat's context.xml in order to configure tomcat's session manager for registering to memcached nodes?

Answer 1

Memcached servers have no knowledge of 'clients'. They don't even know about other memcached servers. Memcached clients have a configuration for a pool and perform a simple hash algorithm to determine which server to talk to. The only dependency is that all your clients have the same configuration. And you need to change tomcat's context.xml only if instances running memcached services change.