Scheduler Migration Guide

Migrating an app to the CloudFormation backend

This document will guide you in the steps necessary to safely migrate applications to the new CloudFormation backend.

Step 1 - Create the CloudFormation stack

The first step will create the new CloudFormation stack with the ECS/ELB resources created, but without altering the <app>.empire CNAME record.

To perform the first step, run:

$ emp set EMPIRE_SCHEDULER_MIGRATION=step1

Step 2 - Swap DNS

You have two options:

1. Manually remove the <app>.empire CNAME and then proceed to step 3.
2. Manually remove the <app>.empire CNAME, then set the DNS parameter to true in the newly created CloudFormation stack. Use this if you want to test the new stack before completely removing the old ECS/ELB resources.

Step 3 - Remove the old ECS/ELB resources

This will remove the old ECS services, and ELB's.

$ emp set EMPIRE_SCHEDULER_MIGRATION=step2

Step 4 - Finalize the migration

$ emp unset EMPIRE_SCHEDULER_MIGRATION