anchor.diff:  
   Lastly, on the `Connectivity and Security` panel, locate and click on the link for the default VPC security group. You will need to add an inbound security rule, because the database by default does not allow external access. In the panel for this group, click on `Inbound Rules` and select `Edit Inbound Rules`. Next click on `Add rule`. In the `Type` column select `MYSQL/Aurora`. The port will be set to 3306 automatically. In the `Source` column, click on the search icon and select `0.0.0.0/0`. Finally, click on `Save Rules` in the bottom right. Your database is ready to go.
   
  -[2] Edit the configuration script
  +=== Edit the Configuration Script
   
   To set up the EC2 instances you will need to provide them with information needed to connect to the databases. We provide a brief configuration script to simplify this process. The template for this script is as follows:
   
  
positive.code: 
  == Multi-Tier Deployments
  
  
  For production deployments, we recommend a *multi-tier* configuration with two or more EC2 instances and a separate database instance using the `Amazon Relational Database Service (RDS)`. In place of `nginx`, this configuration would rely on an AWS `Elastic Load Balancer (ELB)` to correctly spread the traffic among the various nodes, and also to route traffic to either  Kill Server or KAUI based on the incoming port. This deployment option requires a bit more setup, so we also provide an (easier) way to deploy using https://docs.killbill.io/latest//aws-cf.html[CloudFormation templates]. However, the multi-tier option provides more control over the deployment.
  
  The diagram below illustrates the multitier configuration. This section will explain how to setup this option.
  
  image:https://github.com/killbill/killbill-docs/raw/v3/userguide/assets/aws/multi-tier-ami_deployment.png[align=center]
  
  [1] Setup the Database
  
  The first step is to setup the RDS instance. This process begins with the RDS dashboard, which is distinct from the EC2 dashboard. If you are on the EC2 dashboard, select the `Services` menu at the upper left, then scroll down and choose `Databases/RDS`. When the dashboard appears, select `Databases` from the left menu, and click the red button at the top right that reads `Create Database`:
  
  image:https://github.com/killbill/killbill-docs/raw/v3/userguide/assets/aws/multitier-create-database.png[align=center]
  
  You will be taken to the `Create Database` page. The first choice you will have is between `Standard Create`, which allows you to set a full range of configuration parametera, or `Easy Create`, which sets most of these parameters to defaults. We recommend `Easy Create` in most cases.
  
  image:https://github.com/killbill/killbill-docs/raw/v3/userguide/assets/aws/multitier-standard-or-easy.png[align=center]
  
  
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  image:https://github.com/killbill/killbill-docs/raw/v3/userguide/assets/aws/ELB-configure-security.png[align=center]
  
  If you have selected the HTTPS protocol, you will now be required to create or provide an X.509 SSL Certificate. There are many ways to do this. Some are discussed below. If you are using HTTP, continue here.
  
  
  
  
  
  == Configuration
  
  === SSL Certificates
  