What Is Cloud Migration?

Cloud migration is a digital transformation initiative where an organization reconfigures its IT resources to rely on cloud resources for some form of data migration to relocate company data and applications to a cloud service provider’s platform.

An enterprise operating its private network infrastructure may choose to migrate its operations to the cloud and reduce its infrastructure costs and management. They would identify a suitable cloud service provider and migrate their applications and data to the CSPs infrastructure, but not necessarily as a complete migration. Compliance requirements may demand some special cloud configurations, and enterprises can choose a hybrid cloud configuration, thereby securely sharing their private cloud with a public cloud provider in partial data migration to the CSP, all while maintaining sensitive data on-premises.

Later, successful enterprises may outstrip their current cloud service provider’s capabilities and must look for alternatives. Equally so, diversifying over several different CSPs to ensure redundancy may prompt a search for partner alternatives and the enterprise may simply manage multiple CSP relationships in their pursuit of better service uptime and quality. In each case, data must be transferred.

Though there is a high level of standardization with most leading cloud platforms, migrating applications and data still requires a sophisticated level of integration between CSPs for a successful and seamless migration.

Cloud providers also act as a capacity option for enterprise systems. In peak times, when workloads can inundate an enterprise system, local systems can take advantage of the cloud’s flexible capabilities by invoking cloud bursting, where network traffic is routed to cloud resources, virtually on standby, to help carry extra server load.

Even with leading cloud provider migration tools, planning must precede every cloud migration. Without adequate forethought, IT teams can be hampered by several common cloud migration challenges.

• Data Integrity and Massive Databases — Enterprise data is undergoing exponential growth. The size of data and the fact that data migration takes place over physical transit lines prone to interference may lead to data loss during migration. Data must undergo integrity checks during and after migration to ensure a complete data transfer free of errors and holes. In some cases, for the security of simply the size of data, a data backup on a physical storage device can be couriered to the cloud provider for upload to the cloud. Today, leading CSPs are offering secure appliances for petabyte-sized data relocations.
• Downtime — A large part of cloud migration is scheduling. Choosing the right time to perform a cloud migration, especially if critical systems must be brought offline, can save the company money, and user anguish. Typically, cloud migrations are performed during low bandwidth hours, and usually cutovers are not in a single final go, but migration is performed over several syncing intervals, and checks are performed before the final cutover.
• Application Interoperability — During cloud migrations, legacy apps may struggle with cloud environment interoperability. While it is a cloud advantage to be working with the latest innovative platforms, organizations that rely on outmoded software may be faced with refactoring or porting legacy data to a new software package.

The movement of any significant portion of IT resources to the cloud or amongst cloud providers is a cloud migration.

• Cloud Service Provider Migration — The migration of data between cloud providers is cloud service provider migration. The reasons for choosing one cloud provider over another vary, but many drivers include better reliability, cost comparison, diversification, redundancy, and growth. Vendor lock-in is a situation that occurs when a cloud consumer tries to migrate, but a circumstance prevents it, either cost or inability to export data. It is advisable to understand what format your data will be stored in and the CSP’s protocols for data migration.
• PaaS or SaaS Migration — These two migrations can be quick but do deserve special attention. SaaS migrations involve porting application data to a new SaaS or cloud application. PaaS migrates an app and its data to a new virtual machine but beneficially may cost less in subscription fees. For example, for a SaaS email migration, the mailboxes from the local exchange would be migrated over to the SaaS app, whereas, in a PaaS email migration the local Exchange server, with all the mailboxes included, would need to be exported and then imported into the CSPs virtualized platform.
• Database Migration — Quite common in the cloud space is database migrations, so much so that the leading providers, like Azure, and AWS, offer database migration services. Cross-service migration tools will help organizations move from one database to another, e.g. from Oracle to SQL Server or PostgreSQL to MySQL.

Cloud-native capabilities are in many ways better than legacy capabilities. The ease of flexibility and scaling is usually top of mind when considering storing data in the cloud. But migrating legacy applications to the cloud may prove more challenging if cloud providers cannot support an environment for those applications. When addressing the lack of appropriate hosting environments for their business applications, organizations need to consider the necessity for these applications, if they’re vital but incompatible, companies have several strategies to follow to try and remedy the issue:

• Rehosting — Rehosting is the most popular approach to migrating applications. Legacy apps that are incompatible with modern cloud environments will have to follow a different option below, however, most modern application code bases will easily port to other leading cloud providers.
• Revising — Environment incompatible legacy apps can undergo a partial rewrite to bring incompatible features in alignment with cloud support. After revising the app, then it can be hosted on a CSP platform.
• Refactoring — True legacy applications may simply be so outdated that the systems that run them are decades out of production. In these cases, and many others, refactoring business-critical applications is the only option. A complete rewrite can be advantageous, though expensive because the legacy app can be written to utilize cloud-native technologies that are superior to older systems.
• Replacing — Much like refactoring, replacing intends to do away with the old code but keep the functional role of the application. Today, the SaaS space has thousands of vendor cloud applications that can replace many antiquated software packages with updated and more efficient versions. If the business logic is common, like accounting or sales software, replacing on-premise software with SaaS solutions may be the best and least expensive route.
• Retiring — Faced with migrating huge volumes of data to the cloud, companies are provided an opportunity for evaluating the relevance of their software by asking which ones truly support the business. Beyond cutting costs, companies should evaluate their processes as well for redundancy. With careful reflection, migration can be a strategic inflection point for improving overall systems. Discard the applications that serve no purposes, or which features are obsolete, redundant, or unutilized.