How To Migrate Any Cloud Application With Minimal Downtime

Video

About the Talk

Don’t get stuck with a cloud provider just because you don’t know how to escape! Learn how to migrate with confidence and perform a low or zero-downtime cloud migration of all or part of any application.

What You’ll Learn

• How to audit your infrastructure in preparation for a cloud migration
• How to effectively plan and execute a migration
• How to build applications with possible future migration in mind

This Talk Is Designed For

Business leaders and entrepreneurs who want to avoid vendor lock-in by understanding how software applications move between cloud providers.

Prerequisites

Knowledge of web technologies and Infrastructure as a Service (IaaS) products.

Resources

Slides

Migration Checklist

1. Verify lower TTLs have propagated
2. Verify code (stateless services) has been deployed on new host
3. Verify stateful services are ready to receive state on new host
4. Change connection strings on all NEW services to point to new host
5. Change connection strings in codebase to point to new host*
6. Disable writes on all stateful services*
7. Download current state from old host
8. Upload current state to stateful services on new host
9. Perform testing on new host for final verification
10. Point public DNS to new host*
11. Re-enable writes on new host*

*Indicates a step NOT taken during migration dry runs

Key Terms

Migration is moving code and state from one physical location to another.

Code is the stuff that doesn’t change unless you deploy something new.

State is the data your application creates as it runs. It’s customer accounts, uploaded photos, product descriptions, anything that your developers didn’t put in their version control system (probably Github).

Read-Only means a service can still respond to requests for data, but can’t make changes to its dataset.

Latency is the time it takes for packets to traverse the internet between physical machines.

Time to live (TTL) — All DNS records have this one value in common: TTL, which determines how long the record can remain cached before it expires.