Run J2EE with AWS EC2 & RDS

Process of setting up a web app running with Wildfly and PostgreSQL using AWS EC2 & RDS.

1. create an AWS account, and login (all AWS service uses below  are applicable to free-tier users)

• select your country & region to make sure the billing is correct

2. setup an EC2 instance

• Instance Type: t2.micro
• OS: Centos 7
• Subnet: choose anyone in the dropdown list, but remember to pick the same one when setting up the subsequent RDS instance
• Storage/Disk: select Magnetic or SSD, check the option of "Delete on Termination" to avoid extra charges
• Security Group: allow minimum rules for access, port numbers needed: 22, 8080, 5432
• Key Pair: download and change permission to 400
• Connection: using ssh with key auth

3. setup the RDS instance

• Instance Type: PostgreSQL (enable free-tier use only)
• Storage: 20GB by default
• DB instance identifier
• Master user name (username of a postgres db user)
• Availability: public
• Zone/Subnet: same as EC2 instance's
• Security Group: allow access of IPs that needs connection to this DB, eg. current IP, EC2's IP/Subnets(eg. 172.31.0.0/16), port 5432
• Database Name
• finish the setup
• edit the instance properties -> Parameter Group -> New -> put a group name -> changing the property of "max_prepared_transactions" to the value of 300
• connect to the RDS instance using ssh to test the db, command: psql --host=[your RDS instance's DNS] --dbname=[your database's name] --user=[your database's user]
• you may need to reboot the RDS instance to apply any immediate changes

4. Configure the EC2 instance, install software

• connect to EC2 using ssh & key pair using the centos user
• switch to root user
• change the instance timezone to reflect your region
• install Java 8, setup $JAVA_HOME
• install Apache Maven, setup mvn variables
• install Wildfly 11
• install git and folk the destined repository

5. Configure the git repository, and run it with Wildfly as a J2EE Project

• change the start_webapp.sh to let Wildfly's variables inside reflect your instance's configurations, mainly $JBOSS_HOME
• change Wildfly's standablone.xml for a datasource setting reflecting your RDS instance's, this includes the RDS's instance DNS, DB name, DB connection user name and password
• change  the start_webapp.sh add -b 0.0.0.0 to allow public access to Wildfly server
• start Wildfly server using start_webapp.sh, and visit your project's home page through browser on port 8080

6. Stop the EC2 instance & RDS instance,

• you may also delete these in case further charges apply, remember to check your billing dash board for fees & credits incurred.