Zero-downtime deployment pattern in Terraform - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main goal of the zero-downtime deployment pattern?

To update applications or services without interrupting user access or causing service downtime.

intermediate

How does blue-green deployment help achieve zero downtime?

It runs two identical environments (blue and green). Traffic switches from the old to the new environment only after the new one is fully ready.

beginner

What role does a load balancer play in zero-downtime deployments?

It directs user traffic to healthy instances and can shift traffic gradually to new versions without downtime.

intermediate

Why is health checking important in zero-downtime deployments?

Health checks ensure that only healthy instances receive traffic, preventing users from hitting broken or incomplete deployments.

intermediate

In Terraform, what resource type can help manage zero-downtime deployments for compute instances?

Resources like 'aws_autoscaling_group' or 'google_compute_instance_group_manager' can manage rolling updates to avoid downtime.

Which deployment strategy involves running two identical environments and switching traffic between them?

A Recreate deployment

B Canary deployment

C Shadow deployment

D Blue-green deployment

Blue-green deployment uses two identical environments and switches traffic only after the new one is ready.

What is the purpose of health checks during zero-downtime deployment?

A To backup data automatically

B To speed up deployment time

C To verify instances are ready before receiving traffic

D To delete old instances immediately

Health checks ensure only healthy instances receive traffic, preventing downtime.

In Terraform, which resource helps perform rolling updates to avoid downtime?

A aws_autoscaling_group

B aws_s3_bucket

C aws_lambda_function

D aws_vpc

The aws_autoscaling_group resource can manage rolling updates to maintain availability.

What does zero-downtime deployment aim to prevent?

A Faster deployment times

B Service interruptions during updates

C Increased server costs

D Manual configuration

Zero-downtime deployment prevents service interruptions during updates.

Which component typically shifts user traffic between old and new versions in zero-downtime deployments?

A Load balancer

B Database

C Firewall

D DNS server

Load balancers direct traffic and can shift it gradually to new versions.

Explain how blue-green deployment works to achieve zero downtime.

Think of having a backup environment ready before switching.

Describe the role of health checks and load balancers in zero-downtime deployments.

Consider how traffic is managed safely during changes.