Companies of all sizes and across all industries are making a journey from on-premise environments towards cloud computing. This migration to the shared use of resources allows businesses to access virtually endless compute and storage capacity at a fraction of the cost associated with on-site infrastructure.
On-premise to cloud migration is shifting digital assets – like data, applications, and workloads – from on-site data centers to remote, vendor-owned cloud infrastructure. Cloud migration can be complex, and not all companies can go all-in on the cloud at once. For most, it is an iterative journey.
Dgtl Infra takes a deep dive into the on-premise to cloud migration process along with its key business benefits and challenges. We also explore different cloud migration methods and tools, as well as offerings from major cloud service providers (CSPs), like Amazon Web Services (AWS) and Microsoft Azure, to help companies devise the right strategy for their unique business and IT needs.
What is On-Premise to Cloud Migration?
An on-premise data center is one that a company owns and operates within its organizational premises. Cloud, on the other hand, refers to data centers that a third-party owns, manages, and makes available for other companies to use the resources of. Companies can access cloud infrastructure and services over a private or public (i.e., internet) network connection.
On-premise to cloud migration is when a company moves its data center capabilities from on-site facilities to cloud-based infrastructure owned by a cloud service provider (CSP) such as Amazon Web Services (AWS), Microsoft Azure, or Google Cloud. Data center capabilities can include servers, networking equipment, application software, business process services, and infrastructure software.
Businesses and enterprises are increasingly conducting on-premise to cloud migrations to leverage the agility, scalability, and cost-effectiveness of the cloud. However, many businesses still maintain their on-premise data centers for privacy, regulatory compliance, better performance, and customization needs. Such businesses also have the option to adopt:
- Hybrid Cloud: allows migrating some data center capabilities to the cloud while still maintaining on-premise facilities (READ MORE)
- Hosted Private Cloud: provides a single-tenant cloud computing alternative in which the underlying infrastructure is hosted and maintained by a CSP but utilized by a single business
- Virtual Private Cloud (VPC): operates effectively like a hosted private cloud, but essentially, it is a logically isolated space within a multi-tenant public cloud environment
READ MORE: Private Cloud – What is it? and How Does it Work?
On-Premise to Cloud Migration Case Study
Gartner predicts that enterprises’ $1.3 trillion IT spend on on-premise to cloud migration in 2022 will likely increase to $1.8 trillion in 2025. In addition to cloud spending, the number of organizations shifting their data, applications, and operations to the cloud is also increasing rapidly.
According to IDC’s Worldwide and U.S. Datacenter Installation Census and Construction Forecast, the data center industry is quickly becoming a data provider industry, with the percentage of cloud-based data centers predicted to increase from 29% in 2019 to 49% in 2024.
Recently, Capital One shifted its 8 on-premise data centers to the AWS cloud, becoming the first U.S. bank to undergo a complete cloud migration. Moving to the cloud has enabled Capital One to access virtually unlimited compute and storage resources on-demand and on a “pay-per-use” basis. The bank can now manage data at a larger scale and perform compute-intensive data analytics to deliver personalized customer experiences in real-time.
Outsourcing infrastructure provisioning and management allows Capital One to focus exclusively on business-critical services and innovation. The bank now releases new code multiple times a day, instead of quarterly or monthly application updates, and can set-up a development environment in minutes instead of months.
Overall, Capital One has also managed to reduce disaster recovery times by 70% and transaction errors by 50%.
Why Move from On-Premise to Cloud Computing?
On-site data centers offer limited compute and storage capacity and can be costly to set-up, maintain, and scale. Costs and complexity multiply when backup and disaster recovery capabilities are factored in.
Conversely, cloud computing allows companies to access as much compute and storage resources as needed – instantly and without investing in dedicated hardware or additional IT staff.
Benefits of On-Premise to Cloud Migration
Below are five key benefits businesses experience with on-premise to cloud migrations:
With the cloud, businesses can scale compute and storage capacity on-demand without purchasing and configuring physical servers and supporting infrastructure. They also do not need to acquire software licenses for new servers. Many public cloud service providers (CSPs) offer auto scaling, meaning resources automatically scale up or down with fluctuating demands, such as during seasonal traffic surges.
READ MORE: Top 10 Cloud Service Providers Globally in 2023
Cloud reduces capital expenditure and maintenance costs as businesses do not require on-site, physical infrastructure and the supporting staff. Major CSPs provide cost optimization tools and services to ensure businesses do not overspend on resources they do not need. Additionally, the public cloud and its services are often designed with business continuity and disaster recovery in mind, which could otherwise multiply costs for individual businesses.
The cost-effectiveness of the cloud is sometimes considered debatable when a company has already invested heavily in an on-site data center. However, companies can still save incremental costs as they would not have to invest in additional infrastructure as their business grows or in anticipation of occasional demand spikes. Ultimately, companies can provision or de-provision resources on-demand while paying only for what they consume.
Most cloud environments are typically secure and comply with major industry standards and government regulations, such as the Payment Card Industry Data Security Standard (PCI DSS) and the European Union’s General Data Protection Regulation (GDPR). Furthermore, the cloud has access to sophisticated tools and solutions that many businesses, especially small- and medium-sized businesses (SMBs) and start-ups, cannot afford. Major CSPs also provide native security, identity & access management, disaster recovery, and compliance solutions.
As businesses expand geographically and with remote & flexible working, accessing data and applications hosted in on-site data centers remotely, adds considerable latency because of physical distance. In contrast, the cloud allows companies to extend their reach and host websites and applications in locations near their employees and end users, no matter where they are.
5) Faster Time-to-Market
In addition to compute and storage, CSPs offer pre-built applications and services that facilitate rapid innovation and experimentation. Such applications were previously out-of-reach for small- and medium-sized businesses (SMBs), but now they can respond to changing market trends and customer demands faster, by instantly tapping into their CSP’s cutting-edge, cloud-native technology stacks.
READ MORE: Green Cloud Computing, Data Centers and Technology
Challenges of On-Premise to Cloud Migration
Cloud migration is a complicated process and requires careful analysis, pre-planning, and cloud expertise. Ultimately, the benefits and return on investment (ROI) of the cloud depend on how an organization overcomes the following cloud migration challenges:
1) Cloud Migration Planning
Planning a migration requires complete visibility and understanding of all organizational resources and workloads, along with their dependencies. Organizations need to determine which workloads are better suited for the cloud, based on factors like bandwidth requirements, data volume, and security & compliance.
2) Cost Management
Cost overruns are common with on-premise to cloud migrations. While the cloud can decrease the upfront costs of adding new infrastructure and technology, companies tend to underestimate the cost associated with bandwidth and resource provisioning for the migration, as well as ongoing post-migration processes.
3) Hidden Dependencies
Applications and databases sometimes have complex dependencies with other on-site servers, services, and databases. Without careful planning, companies may overlook critical application dependencies during iterative cloud migrations.
4) Security and Compliance
The cloud’s shared responsibility model means organizations must ensure correct configurations and access controls themselves. Managing security configurations during cloud migration, across hybrid and multi-cloud environments, can become complex without adequate expertise, tools, and services. To this end, mismanagement can create vulnerabilities and jeopardize cloud security.
5) Data and Service Downtime
Cloud migration downtime is often inevitable to ensure data consistency and depends on the volume and sensitivity of data, as well as the number of users. Cloud migration services and techniques like continuous synchronization and migration, which take place after normal working hours, can minimize, but not necessarily eliminate, downtime.
How to Manage On-Premise to Cloud Migration
Below we discuss the methods, strategy, tools, and services behind successfully managing an on-premise to cloud migration.
Methods for On-Premise to Cloud Migration
Organizations can choose between two cloud migration methods – online and offline:
- Online Cloud Migration: all data and applications are transferred to the cloud via a network connection, such as the provider’s direct connection or the internet
- Offline Cloud Migration: data and applications are transferred physically to the cloud via portable storage media
Online migrations can be simpler, faster, and cheaper. However, offline migration may be necessary in some instances. For example, if data volumes are enormous (e.g., petabytes), the network connection is unsecured / unreliable, or if the cloud service provider (CSP) does not support online migration for certain workloads.
READ MORE: What is Data Gravity? AWS, Azure Pull Data to the Cloud
Strategy for On-Premise to Cloud Migration
A cloud migration strategy establishes migration goals, timelines, costs, and challenges. Organizations need to determine which workloads to transfer to the cloud, along with the services and applications they must purchase afterward. A comprehensive cloud migration strategy also includes risk assessments, security considerations, and backup & data recovery strategies.
Organizations can choose between the following approaches, identified by Gartner as the “5 Rs”, as a part of their cloud migration strategy:
- Rehost: shift applications, data, and workloads from an on-premise data center to the cloud, as-is
- Revise: modify some aspects of applications to better suit the cloud before migration. The overall application logic and architecture remains the same
- Refactor: re-architect the application to realize the full potential of cloud features and functionality
- Rebuild: redesign and rewrite the entire application to make it compatible with the cloud
- Replace: discard the existing application entirely and replace it with a cloud-native alternative
Organizations can decide between these different strategies based on their existing investments, architecture, and staff capabilities.
Tools and Services for On-Premise to Cloud Migration
Major cloud service providers (CSPs), like Amazon Web Services (AWS), Microsoft Azure, and Google Cloud, offer a multitude of tools to simplify, accelerate, and monitor the cloud migration process. These providers also have services to help organizations follow cloud ‘best practices’, achieve cost optimizations, as well as improve security and performance.
For example, there are cloud cost calculators to help budget cloud migrations and discovery tools to ensure hidden application dependencies do not go unnoticed. Alternatively, organizations with in-house expertise can also choose various open-source tools that are customizable and often free to use.
AWS – On-Premise to Cloud Migration
How to Migrate from On-Premise to AWS?
Organizations can approach on-premise to Amazon Web Services (AWS) migration as a three-phase, iterative process:
- Assess: involves evaluating the organization’s cloud-readiness, identifying business goals, and establishing KPIs for the AWS migration journey
- Mobilize: requires businesses to focus on achieving cloud-readiness and developing cloud skills
- Migrate & Modernize: entails rehosting or refactoring, migrating, and then, validating the migrated applications. In doing so, organizations move away from legacy systems and continually evolve towards a modern, cloud-based operating model
What Services in AWS are Used to Migrate from On-Premise to Cloud?
AWS offers a comprehensive portfolio of tools and services to automate migration processes and provide real-time, intelligent recommendations based on AWS machine learning.
Below are AWS services, including several from the AWS Free Tier, that organizations can leverage to simplify and expedite their cloud migration:
- Migration Evaluator: delivers accurate, data-driven recommendations for choosing optimal compute, storage, and software options based on resource utilization and total cost of ownership (TCO)
- AWS Migration Hub: centrally tracks migration status for all applications and allows organizations to choose the right migration tools and track key performance metrics across them all
- AWS Application Discovery Service: automatically discovers application dependencies
- AWS Management and Governance Services: allow organizations to embrace innovation while maintaining control and compliance
- AWS Application Migration Service (MGN): allows rapid rehosting of a range of on-premise and cloud-based applications to AWS while maintaining consistent operations
- AWS Server Migration Service: enables quick, large-scale workload migration via server snapshots
- AWS Database Migration Service (DMS): allows database migrations while ensuring data consistency and minimal downtime
- AWS Managed Services: organizations can handover ongoing cost optimizations and infrastructure operations to AWS
Additionally, AWS has several tools for migrating data and files that fit all needs, including AWS DataSync, AWS Snow Family – consisting of AWS Snowcone, AWS Snowball, and AWS Snowmobile – and AWS Transfer Family to migrate file transfer workflows (SFTP, FTPS, FTP) to AWS.
READ MORE: Amazon Web Services (AWS) Regions and Availability Zones
Azure – On-Premise to Cloud Migration
How to Migrate from On-Premise to Azure?
Microsoft also recommends using a three-phase approach to migrate data and workloads to Azure, applying the following process:
- Assess: discover assets and dependencies and evaluate different cloud migration strategies
- Migrate: transfer data and workloads through the chosen cloud migration strategy
- Optimize: use built-in tools and services to optimize, govern, and secure applications in Azure
What Services in Azure are Used to Migrate from On-Premise to Cloud?
Microsoft Azure offers numerous tools and services to ensure a smooth cloud migration. Azure integrates all of these tools in its comprehensive migration service, known as Azure Migrate. Specifically, Azure Migrate acts as a central hub and includes:
- Discovery and Assessment: helps discover and assess on-site physical and virtual servers and their interdependencies, estimate costs, and devise optimization strategies for migration
- Server Migration: enables migrating physical and virtual servers to Azure
- Data Migration Assistant: assesses SQL servers to identify incompatibilities with the cloud
- Database Migration Service: provides a simple and straightforward tool to migrate databases to the cloud with minimal in-house expertise
- Web App Migration Assistant: helps in assessing and migrating on-site websites
- Data Box: physical appliance that assists in migrating large volumes of offline data (up to 800 terabytes) for maximum speed and security
Additionally, Azure Migrate integrates with many independent software vendor (ISV) tools for assessing and migrating on-site servers and workloads.