云迁移电子指南：规划与执行成功的云迁移策略

Plan and execute successfulcloud migrations Michael FitzgeraldSr. Director of EngineeringFlexential Professional Services Introduction Cloud migrations have many variables and moving parts, withplenty of opportunities for something to go wrong. However,there are best practices that can significantly eliminate risk. Cloud computing is a model forenabling ubiquitous, convenient,on-demand network access toa shared pool of configurablecomputing resources (e.g., networks,servers, storage, applications,and services) that can be rapidlyprovisioned and released withminimal management effort orservice provider interaction. Those best practices include asking what is beingaccomplished and why a move to the cloud is being made,understanding common pitfalls and how to avoid them, andusing a low-risk process influenced by deep discovery and yourcloud strategy and workload placement objectives. This guide combines the perspectives and information neededto successfully prepare, plan, test, and execute a low-risk cloudmigration and maximize the cloud’s potential. —NIST Special Publication 800 - 145 Michael Fitzgerald Sr. Director of EngineeringFlexential Professional Services Your motivation is your migrationsuccess criteria The answers to “Why do we want to move to the cloud?” are critical for a successful cloudmigration. These answers become your measurement criteria for success and key factorsin determining migration and workload modernization approaches. Understanding theexpected benefits of the migration helps determine the migration process. Cost savings Removing the dependency on dedicated, purchased hardware removes manymaintenance and lifecycle costs. In many on-premises and colocation environments,compute resources are currently overprovisioned. Cloud compute resources can be easilyadded and removed, resulting in cost savings when those resources are well managed. Agility, scalability, and flexibility The dynamic nature of cloud computing allows an organization to change its environmentquickly to meet customer demands and market conditions. Organizations can modernizecode and deployment models to be more dynamic—instituting containerization andautomated scale-on-demand capabilities. Enterprise application leaders often pursue modernization or cloudmigration efforts without determining why and how an applicationposes an obstacle to digital business—leading them to select anapproach that does not resolve the underlying problem.” —Gartner How to Choose the Right Approach for Application Modernization and Cloud Migration Improved access and collaboration With cloud services, especially SaaS, workloads, applications, and data are available fromanywhere. Users are no longer required to connect to VPNs, use remote desktop or VDI,or be in a specific physical location. Organizations have seen productivity increase andstreamlined processes by simplifying access and sharing resources. High availability (HA), disaster recovery (DR) and data protection HA is architected and built into cloud infrastructure, and most providers can provideSLAs of at least 99.999%. Because of the pay-for-only-what-you-use model, cloud-based DR environments are significantly less costly to run than hardware-based DRenvironments. Additionally, many cloud providers offer managed backups anddisaster recovery services. Security and compliance Cloud providers constantly adapt their security procedures, policies, and controlsbased on the ever-changing security and compliance landscape. Depending on thecloud subscription, providers are responsible for security updates and monitoringmanaged components, offloading these to the cloud provider’s responsibility. Mergers, acquisitions, and divestitures Some organizations grow their cloud presence through mergers and acquisitions,during which the question of integrating the acquired cloud infrastructure with existingenvironments often arises. When considering possible divestiture, migrating a businessunit to a dedicated cloud environment can simplify the sale and split of this infrastructure. Data center consolidation Running multiple on-premises or colocation environments generates high managementoverhead and cost. Data center consolidation can reduce this burden for an organization.Still, it can sometimes introduce user performance and reliability issues if those datacenters serve region-specific users or customers. With cloud environments offeringregional data center presence, organizations can maintain regional distribution to retainperformance and geodiversity. Common challenges to avoid failedmigrations or adoption Critical questions for asuccessful migration A successful migration also avoids common challenges that lead to failedmigrations or cloud experiences. It is important to ask questions anddocument what success means foryour organization. Some of theseanswers may be clear early in themigration process, while othersare answered by performing theprepare, discover, and