Application migration to the cloud: Best practices and real-life cases

Today, almost every company leverages cloud services for application deployment. Many businesses adopt a cloud-first strategy and build apps right in the cloud to achieve scalability, availability, cost efficiency, and increased performance. The 2024 state of SaaSOps cloud report from BetterCloud predicts that 85% of all business software will be cloud-based in 2025. Besides, by this year Statista research shows the global cloud applications market is expected to reach $168.6B.

Adapting apps that were not developed as cloud-native ones is a complex process that requires a thorough strategy. Many businesses are not sure how to approach cloud application transformation and make it successful right from the start. So, how to understand if you need software modernization? And where to start with application migration to the cloud? Let's discover the ins and outs of cloud application transformation together.

How to approach app migration to cloud: 7 essential tips

Migrating an application to the cloud is a complicated procedure that involves many risks. If not done right, it can lead to unexpectedly high costs, security gaps, downtime, and poor performance. Here, we highlight several best practices that will help you achieve success with application migration to the cloud:

1. Create a clear migration plan

Before moving applications to cloud, the migration readiness assessment should be performed, and a clear cloud migration strategy designed. It is crucial to understand your current state of the cloud journey, identify areas of strength and weakness, and create an action plan for effective cloud migration. Your plan should include cost estimates, timelines, services to use, etc.

2. Assess and prioritize your apps

As a part of your migration readiness assessment, it is essential to carry out a careful analysis of your application portfolio:

1. The types of applications selected for migration should be defined, including mission-critical, business-critical, customer-facing, and other non-critical applications. Each application's requirements for response time, latency, and downtime should be assessed to determine if these parameters can be slightly compromised during migration.
2. Any legal or other considerations preventing an application's migration to the cloud should be checked, as not every legacy application is suitable or cloud-ready.
3. Data residency requirements should also be reviewed to identify any restrictions on the geographical locations where cloud data can reside.
4. The applications should be prioritized based on which types should be migrated first, which can follow, and which cannot be migrated at all.

For example, if an application is mission-critical, it should have the lowest priority for cloud migration because of the uncertainty of the new infrastructure. Non-critical apps, by contrast, are good candidates to kick off the migration.

3. Evaluate the IT architecture and design of your apps

When it comes to application migration, many CIOs claim that the complexity of their current IT architecture poses one of the major risks of moving to the cloud. Their migration to the cloud is slowed as all the dependencies around business applications, their databases, and the equipment and services that run the applications are too complex to be migrated to the cloud.

If a legacy application relies on a monolith architecture, one should consider the appropriateness of migrating the application to the cloud, considering that few benefits may be extracted from such a setup, potentially at a high cost. Instead, it is better to investigate whether it is possible to modernize such an application to use cloud-ready constructs. They include service-oriented and microservice architectures, as well as deployment models utilizing containers for increased ease of deployment and scalability. In some cases, the most cost-effective solution may be to retain the existing setup.

Containers are great, and even more, they are cloud-agnostic, but serverless and fully managed services are cloud-native, too. With the help of these two options, you can also get all the benefits of cloud-native development, including scalability, flexibility, excellent efficiency, availability, etc.

4. Calculate ROI to assess the migration feasibility

To understand under what circumstances the application migration to the cloud would be profitable for your company, a discovery phase should be conducted, and ROI should be calculated. It is crucial to prepare a detailed app requirements specification and define your goals, features, the optimum technology stack, and architecture overview. Also, it is obligatory to estimate TCO and the profitability you will gain in the short term and the long run.

5. Choose the proper application transformation method

There are various strategies to migrate legacy applications to the cloud. Taking into account classifications by AWS, Azure, and GCP, here at N-iX, we suggest choosing from these seven application transformation methods:

• Re-host (lift and shift): This is the easiest application transformation method, which requires no coding effort and takes the least time. However, from the long-term perspective, this method doesn't offer superior scalability and performance opportunities.
• Re-locate (hypervisor-level lift and shift): This strategy migrates workloads without disrupting operations, rewriting code, or requiring new hardware. It enables enterprises to migrate servers from an on-premises platform, like Kubernetes or VMware, to its cloud version.
• Re-platform (lift and reshape): As a variation of the lift and shift approach, this one involves further adjustments to improve your landscape in some way, like migration to fully managed services.
• Re-factor (re-architect): One of the most complex migration options as it involves re-architecting workloads for cloud-native capabilities. Though resource-intensive, it's the most future-proof approach, enabling features like serverless computing, autoscaling, and distributed load balancing.
• Repurchase (drop and shop): This approach is the best option if the ROI of transitioning a legacy application to the cloud is expected to be poor. In this case, it is better to purchase the ready-made solutions that will bring you the scalability and performance opportunities you require.
• Retire: This strategy involves terminating or downsizing outdated applications by retiring legacy workloads as a first step towards adopting modern, cloud-native deployments.
• Retain: Retaining is used if no migration is needed. It enables keeping applications as-is, where they are.

6. Ensure high-level security of your apps in the cloud

It is crucial to implement security practices from the very beginning of application migration. You may find experienced DevOps engineers and a security team who can make necessary configurations and ensure the long-term security of your apps in the cloud. Here are a few simple things about security in the cloud that everyone should know:

• Encrypting data assets in transit and at rest;
• Leaving sensitive data on-premises, storing it in a particular cloud region, or depersonalizing it;
• Isolating individual workloads to minimize any damage an attacker could cause;
• Configuring a firewall to limit access between different systems;
• Planning for security across heterogeneous environments;
• Avoiding shadow IT;
• Implementing necessary controls;
• Enabling multi-factor authentication and setting up user access policies;
• Utilizing managed identities and service accounts wherever possible;
• Considering cloud-native and cloud-aware endpoint security solutions;
• Implementing a vulnerability tracking program to ensure all applications are updated following manufacturer recommendations.
• Considering the governance and compliance requirements of a cloud environment. It is important to utilize cloud governance tools to control cloud usage.
• Training others on how to maintain security in the cloud.

7. Make use of DevOps best practices (CI/CD, rolling updates, and IaC)

DevOps and the cloud go hand in hand. From infrastructure setup through IAC and CI/CD pipelines to monitoring and security, DevOps helps build a highly automated environment that allows development teams to deliver applications and services at high velocity. DevOps not only boosts development efficiency but also enhances security, speeds up time-to-market, and reduces resource utilization and costs with improved demand-based scalability.

8. Monitor the results and optimize costs if needed

After completing cloud application migration, it is time to start tracking results. Companies should apply metrics and KPIs defined in the planning stage, such as error rates (failed requests/total requests), application availability, latency, number of time-outs, throughput, costs, etc., to assess the success of the application migration to the cloud.

Also, it is essential to improve the DevOps practices used to optimize the costs involved in software development, deployment, and maintenance. These are the most common ones:

• Rightsizing application workloads to make the best use of available resources;
• Considering the use of cloud-native services, minimizing operational overheads and maintenance requirements;
• Automating CI/CD processes and provisioning of IT infrastructure;
• Deleting unutilized instances;
• Taking advantage of autoscaling to deal with both increased and reduced demand. With cloud-native technologies, it may be possible to scale to zero in some cases;
• Moving infrequently accessed storage to cheaper tiers;
• Setting alerts for crossing predetermined budget thresholds;
• Exploring whether hosting in a different region could reduce costs;
• Considering using committed use discounts, usually for periods of 1 or 3 years;
• Leveraging spot instances for parts that don't require high availability;
• Using serverless technologies where possible and appropriate.

Cloud providers offer different computing and storage resources with different payment options and tiers. For example, AWS, which provides computing resources called EC2, allows you to choose different types of instances: Dedicated, On-demand, Spot, or Reserved ones. Choosing the right instance type for a specific case allows for significantly optimized costs.

How to solve the most common challenges during application cloud migration?

Moving applications to the cloud can bring many benefits but may also be challenging for enterprises. Our cloud engineers identified four of the most common pitfalls and shared the ways of overcoming them.

Data loss and corruption

Data loss or corruption can occur during application migration. For instance, network interruptions or hardware failures may cause data loss during transfer, while data corruption might result from improper formatting or inconsistencies between source and target databases.

To minimize these risks, a robust data backup and recovery strategy is essential. This includes conducting regular data backups, verifying data integrity before and after migration, and having a disaster recovery plan ready in case of data loss.

Business disruption

The required downtime for application migration varies based on the software complexity and the chosen migration strategy. For instance, a lift-and-shift migration may cause considerable downtime as the entire application is moved all at once. In contrast, a phased migration, where different components are transferred gradually, can reduce downtime and limit disruptions.

To mitigate downtime impact, it's crucial to schedule the migration during off-peak hours or when business operations will be least affected. Additionally, implementing an IT alerting system to notify relevant technical staff of any issues can help expedite getting the application back online, should the need arise.

Legacy compatibility challenges

Legacy applications may sometimes be incompatible with modern cloud technologies due to their reliance on outdated technologies. Updating the application's code can resolve these issues, but this approach often requires more time and costs.

An alternative solution for applications that cannot be fully migrated is hybrid cloud integration, which links on-premises infrastructure with cloud-based services. This allows businesses to retain the essential capabilities of existing systems while selectively leveraging cloud services to gain additional benefits. Partnering with an experienced cloud consultant can also help you choose the right way to migrate application to cloud.

Security vulnerabilities

Migrating applications to the cloud can also cause potential security risks, especially when moving to a public cloud, which may expose applications to new threats and vulnerabilities. For instance, the new environment might lack the same level of security controls and configurations as the existing one. Additionally, transferring data over the network can increase the risk of interception and attacks.

To mitigate these risks, our cloud security engineers suggest performing a comprehensive security assessment of the target environment and encrypting sensitive data during transfer. Companies must also ensure the new environment complies with relevant security standards and regulations.

Businesses that benefited from application migration to the cloud

• Vable, a UK information management company, wanted to expand its market reach to cover a greater scope of business cases and serve a broader range of customers. Thus, it needed to move its on-premises content automation platform to the cloud to ensure high scalability, availability, and flexibility. N-iX has helped Vable rethink the business idea of their on-premises solution and migrate it to the AWS cloud platform. We have designed a new software architecture, moving from the traditional backend monolith to microservices, developed cloud data services for the product, and built new functionality. As a result, the platform is highly flexible and ready to expand to new markets.
• As a part of its digital strategy, Lebara decided to migrate its solutions from on-premises to the cloud. To avoid vendor lock-in and have more flexibility, our client followed the multi-cloud strategy and chose two cloud providers-AWS and Azure. N-iX has led Lebara's cloud transformation and development of scalable, easy-to-maintain, and cost-efficient cloud solutions. First, our specialists worked on building the microservices on AWS. Our DevOps experts designed and developed a fully automated CI/CD pipeline in AWS. Then, they contributed to the migration from on-premises to Azure. To ensure a precise and automated CI/CD process, the DevOps team designed and developed a fully automated CI/CD pipeline in Azure. Further, we migrated from Azure Service Fabric to Azure Kubernetes Services, which involved migration from Windows to Linux to save costs.
• Our partner, Cleverbridge, decided to migrate its desktop app to the cloud with updated features to ensure that clients on different platforms and devices can easily access the application. N-iX has migrated the old desktop application to the web with its backend integration. We have helped the client go omnichannel to expand market reach. The web-based application is now available across different operating systems, browsers, and mobile devices. The new UX design improved the convenience and experience of using the app thanks to the lean UX approach and involvement of Cleverbridge customers in various stages of the new design. We also applied our extensive knowledge in Power BI and built informative BI analytics for Cleverbridge's largest clients.

Speed up your application migration to the cloud with N-iX

• N-iX is an AWS Advanced Tier Services Partner, a Microsoft Solutions Partner, and a Google Cloud Platform Partner.
• Our expertise in cloud computing includes cloud-native development, on-premises-to-cloud migration, cloud-to-cloud migration, as well as multi-cloud and hybrid cloud management;
• N-iX complies with PCI DSS, ISO 9001, ISO 27001, and GDPR standards.
• With over 21 years of experience, N-iX has successfully delivered more than 200 cloud projects;
• We offer professional DevOps services, including Cloud adoption (infrastructure setup, migration, optimization), building and streamlining CI/CD processes, security issues detection/prevention (DDOS & intrusion), firewall-as-a-service, and more.