Azure and AWS both offer reliable, scalable and secure hosting environments for enterprise workloads in the cloud. Many organisations have already adopted a “cloud first” policy to leverage these benefits and have gone all-in with either Azure or AWS. But what if something changes and a company wants to leave that cloud service provider?
Why Move from One Cloud to Another?
Reasons why users in Azure or AWS would want to switch to the competing cloud service provider include:
1. Changes in the terms and conditions: Initial cloud adoption for enterprises often depends on a unique value proposition offered by a vendor. However, changes in the terms and conditions of a cloud service provider over time could lead to cloud lock-in concerns for organizations.
2. Application portability: Another example of cloud lock-in possibility is the use of heterogeneous platforms used by different cloud vendors which can affect application portability. For example, workloads that use AWS community-contributed Amazon Machine Images (AMIs) or applications configured to make Amazon S3 API calls might limit the ability for enterprises to use other services outside of AWS. In such a case, it might be desirable to migrate out. Another lock-in example is how Azure Site Recovery provides automated mechanisms for moving workloads from AWS to Azure, but requires multiple complex manual steps or third-party tools to migrate in the opposite direction.
3. Contract renewal: Organizations often reevaluate hosting options during the contract renewal period to explore differentiating features offered by competing service providers. With new products and features being introduced by cloud service providers, customers have more choices than ever before to choose an optimal hosting platform for their applications.
4. Cost-benefits: Services offered at premium rates by one service provider could be available at competitive rates with a different provider. For example, Azure Hybrid Benefit along with reserved instances can provide up to 80% cost saving and offers a great value proposition for organizations with pre-existing investments in Microsoft licenses. AWS, on the other hand, provides Microsoft Licensing on AWS, in which customers can use their Microsoft licenses with or without Software Assurance to reduce cloud hosting charges.
5. Compliance standards: The compliance standards to be met for hosting data and application with a cloud service provider or on-premises varies across different industry sectors. Any instance of non-compliance flagged during an audit could lead to re-hosting or migration of application/data to a compliant platform.
6. Data consolidation: In hybrid cloud architectures, a company’s data could exist across public/private clouds or on-premises deployments. Consolidation of data and seamless management is important for optimizing the spend on data storage and operations. One example of this is in the case of M&A (Mergers & acquisitions), where companies with different platforms need to consolidate.
Cloud Migration Challenges between AWS and Azure
Data is the nexus of enterprise IT, and migration from AWS to Azure and vice versa is one of the most challenging aspects when implementing multicloud architectures. Let’s look at some of the challenges.
1. Data Migration: The fact that Azure and AWS use proprietary storage offerings and APIs make the data migration process complex. Leveraging third party tools for data transfer could lead to integration challenges as both the platforms use diverse technologies in the backend. And the entire process of transitioning between the two clouds may not be a feasible option for business-critical applications due to time and cost constraints involved.
2. Secure Data Transfer: Secure transfer of data between Azure and AWS should be done using a process that meets industry-specific governance and compliance standards. Direct download and upload of data can lead to security concerns as the data at rest and in transit should always be encrypted. While Azure Site Recovery offers a feasible solution for large scale secure migration between AWS and Azure, it requires additional infrastructure to be set up in AWS, which may not be feasible in cost-sensitive environments.
3. Access Control Privileges: When data is migrated between AWS and Azure platforms, administrators need to ensure that consistent data access and protection policies are applied in the destination as well. Security and access control are configured using different sets of tools and policies in AWS and Azure. While AWS depends on IAM user policies and resource-based policies for Amazon S3 access, Azure storage uses RBAC assigned to Azure AD users. Hence, redesign and reconfiguration of the entire system might be required to maintain the same level of security after migration. Management of data across AWS and Azure environments using unified tools and interfaces is also a major challenge.
4. Other Challenges: There are a few other additional challenges to the migration process between platforms. It will be necessary to find a way to evaluate the costs and calculate the differences. You’ll also need a way to measure and maintain the same or acceptable performance and SLA’s of different devices, instances, VM’s, storage types, etc. on the new platform.