a handy guide that quickly summarizes various deployment approaches that are adopted by IT industry. There are various approaches that are currently adopted by organizations and it all be confusing for developers, product owners, scrum masters, project and program managers who tend to shuffle between various IT development and deployment teams. This is an attempt to simplify various approaches and also highlight the pros and cons of each approach. Happy reading.

1. Deployment
Strategies
Jahangir Shaik

2. Basic Deployment
Rolling Deployment
Load Balancer
Simultaneous Updates
Instances
Load Balancer
Select Updates
Instances
Basic deployment simultaneously updates newer version on every node
or instance in the target environment
PROS
• Fast
• Simple
• Cost effective
CONS
• Outage vulnerability
• Difficult to rollback
Rolling deployment involves in replacing instances of previous version,
one after other, in a sequence till all instances are updated with newer
version; Also, sometimes known as ramped deployment
PROS
• Flexible
• Minimum downtime
• Flawed deployment
impacts less users
CONS
• Slow rollback
• Requires Backward
compatibility
2

3. Multi-service Deployment
Blue Green Deployment
Load Balancer
Multiservice Updates
Instances
Load Balancer
PROD
STAGE
Blue-green deployment is a release method that has two different but
identical environments wherein one environment is updated with newer
version and when testing is complete, traffic is switched from older
version environment to newer, updated environment
PROS
• Instant rollout /
rollback
• Minimum downtime
• Zero versioning issues
CONS
• High cost
• Difficult to scale
• Distorted user
transactions
Multi-service deployment simultaneously updates every node in the
target environment with multiple services; Similar to basic deployment
but mostly applicable for services
PROS
• Fast
• Simple
• Cost effective
CONS
• Outage vulnerability
• Difficult to rollback
3

4. Canary Deployment
Dark Launch Deployment
Load Balancer
V1
V1
V2 Canary
Load Balancer
V1
V1
V2
New feature
Canary deployment updates an app or service in increments. Initial
update is rolled out to small subset of users, and it is gradually
increased in the scope of users till it reaches 100%
PROS
• Minimum downtime
• Fast rollbacks
• Allows test and live
updates
CONS
• Slow rollout
• Release increments take
time
• Requires High observation
Dark launching process allows production ready release features to a
small user group without exposing to rest of userbase until they are
ready
PROS
• Gain feedback
• Minimize risk
• Safe & fast transition
• Run experiments
CONS
• Large setup timeframes
• High cost of
implementation
4

5. Feature toggle Deployment
Shadow Deployment
Load Balancer
Users
Users
Live Environment
Users
Shadow deployment follows a process wherein app or service changes are
deployed in a parallel environment that mimics the production
environment. The deployed changes are not visible to the end-users,
hence the term “shadow”
PROS
• Efficient scaling
• Real world testing
• Risk mitigation
CONS
• High cost of
implementation
Feature toggle deployment allows a service, function or feature to be
hidden, enabled or disabled during runtime for a particular group of
users while other users don’t notice any impact
PROS
• Rapid feedback
• Unfinished feature can
be deployed
CONS
• High cost of
implementation
• Impacts User experience
Features
Features
New feature
5
Feature visible
Feature not visible

6. Users
Users
Users
Users
A/B test Deployment involves measuring functionality of two versions by
collecting real time data. While not strictly a deployment strategy, it’s a
testing approach that builds on the canary deployment strategy. A/B
testing allows organizations to take informed business decisions
PROS
• Experimentation
• Exploration
• Traffic routing based on
business need
CONS
• High cost of maintenance
• May negatively impact
user experience
A/B Test Deployment
A/B
Testing
15%
30%
Option A
Option B
Option B
6

7. Thank you