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@mlconnor
mlconnor / elastic_beanstalk_external_sessions.md
Created October 17, 2014 20:26
Analaysis and recommendation for externalizing session in Elastic Beanstalk using Tomcat and memcached.

Session Management in an Autoscaling Environment

Problem Statement

User sessions in J2EE and LAMP stacks have traditionally been handled in memory by the application server handling the user request. Because of that, load balancers have been configured to use sticky sessions. By sticky sessions we mean that once the user has visited the site, they will be assigned an app server and will return to that server for subsequent requests. The load balancers typically handle that by referencing the users session cookie.

Elastic cloud environments differ from traditional server configurations in that they have a variable number of servers based on traffic loads whereas traditional configurations had a fixed number of servers. When traffic volumes decline it is necessary to vaporize servers. In doing so, we would lose user sessions (essentially forcing a logout) unless we come up with a new strategy for session management.

A new approach

After much research, it is clear that the best

@Pablosan
Pablosan / ec2_instance_create_and_setup.sh
Created January 30, 2011 23:37
A bash script that will set up a new EC2 instance and ssh into it.
#!/bin/bash
# Authorize TCP, SSH & ICMP for default Security Group
#ec2-authorize default -P icmp -t -1:-1 -s 0.0.0.0/0
#ec2-authorize default -P tcp -p 22 -s 0.0.0.0/0
# The Static IP Address for this instance:
IP_ADDRESS=$(cat ~/.ec2/ip_address)
# Create new t1.micro instance using ami-cef405a7 (64 bit Ubuntu Server 10.10 Maverick Meerkat)