Every time you start/stop, reboot or change the instance type the instance computer name and the private IP address/DNS name is changed. Its possible to set the computer name fixed, but its not possible to set a fixed private IP address unless you take a VPC (also see this post). We are not going to use a VPC because of the costs. Make sure you assign an elastic IP address to a DNS A record, for example connections.lialis.com. Before you start installing Websphere on your server make sure the EC2 pings the A record connected to the elastic IP address correctly. Please give this process a bit time. If you start to quickly installing WebSphere it will use the private IP instead of the elastic IP address and then after you reboot the EC2 Websphere will stop working because the private IP address is changed because of the reboot.
DB2 will stop running when the computer name is changed because of a reboot. After you have created a new instance the first thing you must do is start the EC2ConfigService Settings program and disable Set Computer name. Then change the computer name to something understandable and reboot the Windows server.
Aassign in the AWS Management Console a security group and add the following ports to this group. These ports are needed for the installation of IBM Connections.
25, 21, 80, 81, 82, 443, 444, 8008, 1352, 25, 8642, 450, 83, 389, 9060, 9043, 8879, 8008, 13100, 13101, 13104, 50000
Also in the Windows firewall make an TCP inbound rule with above ports listed under Specific ports.
Add the security group to the instance in the AWS Management Console.
I used this procedure to install IBM Connections.
Note, later on in the guide they switch from wsadmin to wasadmin, keep using wsadmin and you will be fine.