Cloud Migration Overview

 Application migration objective

• Conduct application discovery and assessment 
• Create an approved Azure target architecture
• Complete the Deployment Design Document (DDD)
• Deploy the application in Organization's Azure environment 
• Run tests to prove production readiness

Capture Application Key Stakeholders name form Migration and Application team side:

• Application Team stakeholders
• Migration Team stake holders

Follow Public Cloud Core Six Principles:

1. Secure the Network
2. Monitor the Environment
3. Protect the Data
4. Deploy Infrastructure as Code
5. Control the Access
6. Make the allocation match the demand

Secure the Network

• Private network connectivity to the cloud – Private (VPC) and Public (PaaS) Peering
• Private network connectivity to/from VPCs and PaaS services
• Support for "Bastion” VPC with private satellite workload VPCs using transitive routing from source
• No Internet ingress/egress other than from a designated VPCs
• Micro-segmentation of resources using Network Security Groups

Monitor the Environment

• Common shared logging and monitoring infrastructure
• Proactive notification and remediation
• Mandatory integration with Centralized monitoring solution
• Full data access log capture for traceability
• Support for capture and analysis of network flow logs

Protect the Data

• Defense in depth – multiple layers of protection for all of Organization's data
• Data is encrypted at rest and in motion
• Seamless integration between PaaS services and key management infrastructure
• Encryption keys owned by Organization's policy based and seamless key rotation
• Data Access is limited to known IP address ranges/VPC ids

Deploy Infrastructure as Code

• Immutable infrastructure – pre-built/pre-tested VM images
• Replace, not repair
• Fully automated CI/CD deployment pipeline
• Industry-standard cross-cloud compatible toolchain – Terraform (orchestration), Packer (VM images), Ansible (configuration)
• Limited DevOps access to Production – deployments are automated

Control the Access

• Federation with on-prem Organization's identity realms – IT Services domain 
• Support for legacy authentication and authorization needs (i.e. LDAP, etc.)
• Workflow-based approval process to gain access (i.e. an onprime system)
• Principle of least privileged access with ability to support fine grained access control

Make Allocation Match Demand

• Auto-scaling number of VMs based on request load
  
• Serverless “functions” fully managed by cloud provider
• Containerized microservices running on cloud provider managed orchestration platform (i.e. Kubernetes)
• Auto scaling PaaS services for load balancing, networking, messaging, etc.
• Automatic event triggering that scales according to demand

Follow this migration flow of overall process

Migration Phases at High level you should go through:

Clearly define migration responsibilities in teams

During Kick Off, get the High-level overview of applications

• What does the app do?
• Current state architecture
• Technology stack
• Interfaces and dependencies

Have Migration Timeline: