Application modernization can involve several strategies.
Rehosting (“lift & shift”) and Refactoring, where an existing application is migrated mostly as-is to cloud infrastructure, are quick but miss out on most of the benefits of the cloud.
Rearchitecting and rebuilding, on the other hand, require significant investment to make an application truly “cloud-native” and achieve the highest business benefits from the cloud.
The Cloud Native Computing Foundation (CNCF) explains this in part as:
“Cloud-native technologies empower organizations to build and run scalable applications in modern, dynamic environments such as public, private and hybrid clouds. Containers, service meshes, microservices, immutable infrastructure and declarative APIs exemplify this approach.
These techniques enable loosely coupled systems that are resilient, manageable and observable. Combined with robust automation, they allow engineers to make high-impact changes frequently and predictably with minimal toil.”
What is Rearchitecting an Application?
Rearchitecting applications involves sweeping change where an old monolithic application is completely revamped according to modern microservices architecture.
Tactics also include:
- Retiring old technologies and adopting new ones.
- Rehosting data from an on-premise server to a cloud server.
- Replacing proprietary plugins and tools with industry-standard and open-source ones.
What Does Rebuilding an Application Entail?
Rebuilding applications can be faster or slower than a rearchitecture, just like building a new house can at times be easier than a major renovation depending on a variety of factors.
In both cases, the journey can take weeks or months depending on the complexity of the app and the organization’s openness to change.
Key reasons to justify this level of investment include driving down total cost of ownership and increasing agility, resilience and scalability.
What Key Considerations and Decisions Do You Need to Make Before Modernizing Your Applications?
5 Reasons to Re-Architect Applications for the Cloud
1. Reduce Costs of Ownership
Reducing the hefty cost of traditional IT infrastructure is a key driver for organizations wanting to move resources to the cloud.
Large applications often cost too much when running on legacy hardware-based infrastructure, especially when the requirement to scale-out elasticity can be more easily provided by the cloud.
Further, containers have driven even more cost efficiencies over VMs by enabling organizations to use the standards for a container runtime in Docker, a container orchestration tool in Kubernetes, and tools for monitoring and networking like Prometheus and Istio.
Serverless computing is proving extremely successful at running workloads on a pay-per-use basis where IT has no infrastructure to maintain and developers can focus on running their code on a ready-made cloud platform.
This makes the cost advantages of this model extremely attractive.
Additional benefits of moving to cloud-native include:
- Eliminating the time and costs involved to maintain old infrastructure including private hardware
- Data centre costs
- Proprietary software licenses
When considering all aspects, cloud-native enables much lower total cost of ownership.
2. Drive Agility with the Cloud
Traditional IT includes configuring servers, databases, and networking, all while ensuring end-to-end security. Developers typically wait for environments to be provisioned. Releases are slow due to manual steps, onerous sign off processes, and ensure apps are reliable post-release.
Any feedback or bug fixes often takes days, weeks or even months to be implemented – way too long in today’s real-time world.
Unlike traditional monolith applications, cloud-native applications are composed of small, independently built, tested, and managed microservices. These small code packages are inherently easier and safer to manage than a massive body of code.
This reduces risk and improves developer confidence when introducing change, dramatically improving their productivity.
It also means:
- Release cycles can be streamlined – less code is impacted with a given change.
- Interdependencies are more easily managed through clean service interfaces.
- Fewer people are involved, including business stakeholders.
- Each can be promoted to a production environment once ready rather than having to wait for all others in a traditional big bang release.
As developers become more productive and cloud instances become easier to manage, a heightened level of agility is enabled through new DevOps processes including continuous integration and continuous delivery.
These processes involve incremental development, testing and deployment, aggressive automation, and releasing value faster than ever before. Some organizations are achieving production code releases daily or even many times per day.
This agility afforded by the cloud can drive innovation by allowing experimentation to improve customer experience. Whether it’s A/B testing of new features or canary releases of new versions, a newly flexible cloud-native application makes it possible and easy.
3. Achieve Application Resilience
Monolithic applications are notorious when dealing with failures and issues – typically, any issue in any part of the application sets off a domino effect that takes down the entire app.
Instead, fault tolerance can be built into each microservice.
The advantage of this is that even if a single server fails, its neighbouring services can function normally. This would affect the user experience to an extent but is better than rendering the entire application unusable.
Further, cloud-based instances are managed by cloud vendors that promise ‘five nines’ availability – 99.999% uptime. Even in the rare case of a failed host, you can replicate a backup instance in the cloud, which is much faster than procuring a new hardware.
Finally, cloud vendors provide multiple availability zones so you can quicken performance for every region you serve and isolate faults to particular regions. The cloud enables reliability in a way that’s not possible with traditional on-premise hardware.
4. Enable Scalability
Unable to scale on-premise instances fast enough, large technology companies like Google, Microsoft, Facebook and Amazon began migrating to the cloud over a decade ago and have since achieved true “web-scale” including elasticity and enormous horizontal resource scaling.
Today, those very same benefits can be leveraged by any organization looking to modernize their application stack.
Cloud platforms enable auto-scaling of cloud instances so certain parts of the system can automatically scale out during a traffic spike. Conversely, they can be used to scale down during times of low activity to reduce costs. Other common uses of this elasticity include periods of intense performance testing and data crunching.
Cloud vendors provide automation services like Azure Resource Manager that let you templatize resource creation and replicate the same configuration on multiple instances with a single command.
This brings predictability to resource creation and lets you scale out with ease.
Serverless computing platforms like Azure Functions allow scaling without even having to provision additional instances. Provisioning is done behind the scenes by the cloud – you define the resources required, and your code executes when called automatically in an on-demand billing model.
5. Do Not Compromise on Monitoring and Security
As a system scales it’s easy to compromise on monitoring and security.
This is a recipe for disaster.
Monitoring and security are fundamentally different with cloud-native applications.
Rather than rely on a single monitoring tool, you’ll likely need to take a best-of-breed approach to monitor by using a combination of vendor-provided monitoring tools like Azure Monitor, third-party tools like PagerDuty, and open source monitoring tools like Prometheus.
Security in the cloud requires adequate encryption of data in transit and at rest. The cloud vendors provide encryption services for this purpose. Additionally, open source tools like Calico are enabling policy-based security that is purpose-built for microservices.
Though monitoring and security are more complex and challenging for cloud-native applications, when done right they provide a level of visibility and confidence that is unheard of with traditional monolithic applications running on-premise.
Read More About Application Modernization:
- What Does Application Modernization Mean?
- How to Modernize Applications
- 6 Benefits of Cloud-Native Applications for Business
Modernize Your Legacy Applications for the Cloud
As you modernize your legacy applications for the cloud to meet the changing requirements of your business, it is important to understand the advantages of cloud-native applications.
A simple “lift-and-shift” of an old application – rehosting it in cloud infrastructure – misses out on the benefits cloud-native provides.
Look to a partner skilled in cloud-native development to help you assess your application portfolio and determine which applications warrant these enhanced capabilities.
Architech has over 15 years of experience guiding its clients through the depths of the cloud to unlock true agility, resiliency, and scalability for their legacy applications. Contact us today to receive an Application Modernization Assessment and learn how we can help you find cost-savings on the cloud.