Introduction Designing and Implementing Deployments

In this lesson we cover the essential techniques for designing and implementing reliable deployments in Azure DevOps, preparing you for the AZ-400 exam. You’ll discover strategies to minimize downtime, manage database changes, and adopt advanced release patterns to ensure production stability.

Lesson Roadmap

Deployment Strategies
Designing and Implementing Resiliency
Implementing Deployments with Database Tasks
Dependency Deployments and Pipelines
Minimizing Downtime During Deployments
Designing a Hotfix Path Plan
Load Balancer and Traffic Manager Releases
Implementing Feature Flags
Application Deployment Techniques

1. Deployment Strategies in Azure DevOps

Modern applications require flexible release approaches to reduce risk and improve agility. Azure DevOps supports several deployment patterns:

Strategy	Description	Use Case
Blue/Green	Maintain two parallel environments; switch traffic post-validation.	Instant rollback and zero-downtime updates
Canary	Gradually roll out changes to a small subset of users.	Early feedback and limited blast radius
Ring	Define deployment rings (e.g., internal → pilot → production).	Controlled, phased rollouts
Progressive Exposure	Automate traffic shifts based on metrics and health checks.	Data-driven release automation
Feature Flags	Toggle features on/off at runtime without redeploying code.	Decouple deployments from releases
A/B Testing	Route user segments to different feature variants.	Comparative analysis and user experience testing

Using these strategies, you can align deployments with your organization’s risk tolerance and user expectations.

2. Designing and Implementing Resiliency

Building resilient systems helps maintain availability during failures:

Define Recovery Time Objectives (RTO) and Recovery Point Objectives (RPO).
Apply resiliency patterns: retry, circuit breaker, and bulkhead isolation.
Use Azure services like Traffic Manager, Front Door, and Availability Zones to distribute risk.
Automate health checks, alerting, and rollback workflows.

Note

Implement circuit breakers and retries at both application and service levels to handle transient failures effectively.

3. Implementing Deployments with Database Tasks

Coordinating application and database updates is critical for schema changes and migrations:

The image is a slide titled "Implementing a Deployment That Includes Database Tasks," with a focus on implementing such deployments. It includes a logo and a copyright notice for KodeKloud.

Key best practices:

Use migration frameworks (Entity Framework Migrations, Flyway, Liquibase).
Automate pre-deployment schema validation and post-deployment data verification.
Ensure backward-compatible changes to minimize service interruptions.
Provide rollback scripts or leverage transactional deployments when supported.

4. Dependency Deployments and Pipelines

Large solutions often span multiple services and environments:

Map inter-service dependencies and determine deployment order.
Break pipelines into stages: build, test, deploy, validate.
Implement manual or automated approvals in Azure Pipelines.
Manage infrastructure with code (ARM templates, Bicep, Terraform) for consistency and versioning.

5. Minimizing Downtime During Deployments

High-availability applications must remain online during updates:

The image is a slide titled "Plan for Minimizing Downtime During Deployments," listing two topics: "Overview of Downtime Minimization Strategies" and "Practical Example of Deployment Slots in Azure."

Adopt these approaches:

Rolling updates across instances to avoid full service outages.
Blue/Green and Canary for zero-downtime switches.
Azure Deployment Slots: swap staging and production environments in seconds.
Leverage health probes and automated rollbacks on failure.

Warning

Always validate slot configurations and connection strings after a swap to avoid environment mismatches.

6. Designing a Hotfix Path Plan

A streamlined hotfix process enables rapid responses:

Differentiate hotfixes from standard releases in your branching strategy (Git flow, GitHub flow).
Automate build, test, and deployment pipelines for hotfix branches.
Define approval gates and ensure full traceability from commit to production.
Include rollback capabilities and clear versioning for hotfix packages.

7. Load Balancer and Traffic Manager Releases

Ensure traffic distribution and global fault tolerance:

Service	Layer	Purpose
Azure Load Balancer	Layer 4	Distribute traffic across VMs and scale sets.
Azure Traffic Manager	DNS	Route users based on performance or priority.

Configure health probes, routing methods, and endpoint priorities.
Integrate with Azure Pipelines for automated deployment and validation.

8. Implementing Feature Flags

Feature flags empower controlled rollouts and rapid rollbacks:

The image is a slide titled "Implementing Feature Flags," listing topics such as the definition of feature flags, their uses in software development, and Azure app configuration.

Implementation steps:

Define feature flags and their lifecycle.
Use cases: gradual rollouts, A/B testing, kill switches.
Centralize flag management with Azure App Configuration.
Integrate client SDKs to read and act on flag values at runtime.

9. Application Deployment Techniques

Choose the right packaging and delivery method for your application:

Container-based: Docker, Kubernetes, Azure Container Instances.
Binary archives: ZIP, WAR with Web Deploy or MsDeploy.
Scripted pipelines: Azure CLI, PowerShell, and Azure DevOps tasks.
End-to-end Azure Pipelines: orchestrate build, test, and release jobs seamlessly.

Example: Deploy a Web App using Azure CLI

az webapp up \
  --name MyWebApp \
  --resource-group MyResourceGroup \
  --runtime "DOTNET:6.0" \
  --sku F1

Links and References

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