What to Know When Planning a Hybrid Cloud

Hybrid cloud architecture seamlessly integrates private clouds with public clouds, allowing platform architects to select optimal environments for their applications and data. This approach is ideal for situations where you need access to specialized analytics applications, artificial intelligence tools or unique database technologies that aren't fully supported by a single cloud provider. For instance, an organization might want to harness the data analytics capabilities of Google's BigQuery serverless data warehouse alongside object storage with Amazon S3, ensuring a blend of services that neither provider can offer alone.

The hybrid cloud approach not only enhances scalability, enabling businesses to quickly adapt to changing needs, but it also helps optimize costs by allowing businesses to choose the most cost-effective cloud provider for specific workloads and applications. A hybrid cloud architecture also helps adhere to privacy and compliance requirements by placing data and applications in the most appropriate locations.

However, designing a hybrid cloud from scratch can be challenging. This article introduces you to the various layers that make up a hybrid cloud system and introduces tools that can be helpful if you're considering developing your own hybrid cloud solution.

Let's start by exploring the infrastructure layer.

Infrastructure Layer

The infrastructure layer in a hybrid cloud architecture consists of compute, storage and network resources—the core components necessary for the hybrid cloud operation.

Compute Resources

Compute resources provide the required processing power that allows organizations to run workloads across private and public cloud environments.

Determining the compute resources needed for your hybrid cloud will depend on the specific requirements of your use case. Fortunately, you can integrate the capability to scale resources dynamically into the platform layer (more on that shortly). That means, as a starting point, you can estimate the minimum capacity required by public and private cloud environments to support your workloads while ensuring scalability and redundancy and designate these as base compute resources.

Storage Resources

Storage resources in a hybrid cloud enable organizations to store sensitive data in private clouds across multiple locations within specific geographic regions while using cost-effective public cloud resources for less sensitive data. This helps them adhere to regulatory requirements.

The goal of this layer is to ensure efficient data management and accessibility, leveraging the distributed storage architecture of the hybrid cloud approach.

When designing your storage layer, don’t overlook the egress costs incurred from frequently moving data between public and private clouds, since these costs can greatly affect your overall storage strategy. To avoid unnecessary expenses, you should take a carefully planned approach to data movement and replication to ensure your hybrid cloud storage solution remains cost-effective. For instance, you could take advantage of the ability of some cloud providers to create private connections at the network layer.

Network Resources

The network layer in a hybrid cloud infrastructure is responsible for connecting the private and public cloud environments. It consists of physical appliances and virtual components such as routers, virtual private networks (VPNs), software-defined networks (SDNs), cloud access security brokers (CASBs), gateways, proxies, switches, load balancers and firewalls. The goal is to have these components work as a team to ensure secure, efficient and reliable data flow across the entire hybrid cloud setup.

Given the importance of the network layer in ensuring the performance and integrity of a hybrid cloud architecture, relying solely on the internet to connect your private and public infrastructure is not recommended. Higher latency is a significant concern; the internet cannot guarantee the low-latency connections that are often required for performance-sensitive applications (such as video streaming services). Moreover, data and applications that require real-time processing, like financial transactions and real-time analytics, may suffer from delays that negatively impact user experience and operational efficiency.

The internet's unreliable connectivity poses another challenge. As a public network, the internet is prone to fluctuations in performance and availability. Unlike dedicated connections, which offer consistent and predictable performance, relying on the internet for hybrid cloud connectivity introduces an element of unpredictability that can lead to downtime and reduced application reliability.

Compliance and regulatory challenges are additional reasons to avoid using internet connections for hybrid cloud setups. Many sectors, like healthcare and government, are subject to stringent data security and privacy regulations, necessitating the use of secure and private connections for data transfer. Connecting to the internet makes it more challenging to ensure that data handling and transfer meet regulatory requirements. Here are just a few examples:

• General Data Protection Regulation (GDPR)
• California Consumer Privacy Act (CCPA)
• Health Insurance Portability and Accountability Act (HIPAA)
• Payment Card Industry Data Security Standard (PCI DSS)
• Federal Information Security Modernization Act (FISMA)

The higher egress costs associated with transferring data between private infrastructure and public cloud providers via the internet are another critical factor. Public cloud providers typically charge for data egress when data leaves their network. These costs can quickly accumulate for organizations with significant data transfer requirements, making internet-based connections economically unfeasible.

Overall, while the internet offers a ubiquitous means of connectivity, its use as the primary connection method between private infrastructure and public cloud providers in hybrid cloud setups is fraught with challenges. These factors underscore the need for dedicated, secure and efficient networking solutions within the hybrid cloud network layer to ensure optimal performance, security and cost management.

Build Your Own Hybrid Cloud: Infrastructure Layer

When it comes to building the infrastructure layer, it all comes down to choosing cloud providers that fit the requirements of your use case.

Major public cloud providers (the biggest ones are Amazon Web Services, Microsoft Azure and Google Cloud Platform), offer a wide range of cloud computing services that are scalable, flexible solutions for deploying applications and managing infrastructure.

When setting up private clouds, select a provider that emphasizes the connectivity required to interweave different clouds and on-premises infrastructure instead of one that focuses on highlighting its proprietary solutions and technologies. Equinix is a leading dedicated cloud provider that simplifies the process of creating direct and private virtual connections with major public cloud and SaaS providers. This enables businesses to develop a hybrid cloud setup that merges the native services of public clouds with the security and performance benefits of private infrastructure.

Platform Layer

The platform layer in a hybrid cloud architecture serves as the bridge between the underlying infrastructure layer and the applications running on top. The role of this layer is to abstract the complexity of the hybrid cloud infrastructure, enabling organizations to focus on application development.

Key elements of the platform layer include the operating system, container orchestration, connectivity tools, observability frameworks and GitOps tools. However, this list may increase or decrease depending on your requirements.

Given its role, the platform layer should be designed to provide a consistent and unified environment for applications, regardless of the underlying cloud infrastructure. To accomplish this goal, you should use services and tools that ensure that applications can use the full capabilities of the hybrid cloud, including scalability, flexibility and portability.

Build Your Own Hybrid Cloud: Platform Layer

Since each use case is unique, the list below aims to suggest potential components to include in your BYO platform layer design.

• An operating system is the foundational layer that supports all other software components, ensuring compatibility and stability across hybrid cloud environments. Popular picks include Ubuntu, SUSE Linux Enterprise Server (SLES) and Red Hat Enterprise Linux (RHEL).
• Container orchestration manages the deployment, scaling and operation of containers, facilitating seamless application runtimes across different clouds. Kubernetes is often the best choice, but for projects requiring deploying and managing both containerized and noncontainerized applications across different clouds, HashiCorp Nomad might be worth considering.
• Infrastructure as code (IaC) platforms provide a unified interface for provisioning and managing resources and applications across multiple cloud environments, simplifying operations and governance. If your project is mostly focused on Kubernetes-native applications and services, Crossplane can be a good choice. Alternatively, you could consider Terraform for scenarios less centered on Kubernetes. Here’s an in-depth look at these two choices and how they differ.
• Service mesh tools facilitate secure, efficient and reliable communication between disparate workloads across different environments in a hybrid cloud solution by managing traffic flow, enforcing policies and providing service discovery and encryption. Istio is a popular option that makes it easy to work with both Kubernetes-based and conventional workloads. Other solutions with similar functionality worth considering include Linkerd and Consul.
• API management tools primarily focus on traffic routing, API lifecycle management, security (authentication, authorization and encryption) and API monitoring. Simply put, API management tools facilitate all aspects related to communication between external-facing APIs. Two excellent tools for this are Apigee and Tyk.
• An observability framework collects, analyzes and visualizes telemetry data (logs, metrics and traces) to offer insights into the health and performance of applications and infrastructure. Two widespread, cloud-agnostic solutions in this space include Grafana and Prometheus.
• Cost management tracks, analyzes and optimizes cloud spending to enable effective budget management and cost optimization strategies for hybrid cloud deployments. Two solutions focused on optimizing Kubernetes cost monitoring are Kubecost and CloudZero. If you're looking for a more holistic solution, you might want to consider Datadog's Cloud Cost Management.
• Internal developer platforms (IDPs) empower developers with self-service deployment and management capabilities for applications and services throughout the hybrid cloud infrastructure. Popular choices here include Qovery, OpsLevel and Backstage.
• GitOps automation tools automate operational workflows and processes, reducing manual efforts and increasing efficiency in deploying and managing cloud resources. Two excellent options to consider in this space include Flux and Argo CD.

Keep in mind that your hybrid cloud does not necessarily need all these components, as some may overlap. A valid path is to opt for a unified solution like OpenShift for container orchestration, CI/CD pipelines, security controls and service mesh.

The design of your hybrid cloud depends a lot on your use case, budget and internal requirements. Do you want maximum control and customization in container orchestration? You can use vanilla Kubernetes instead of an opinionated distro like Rancher's RKE2. Keep in mind, though, that more control means more components to set up and manage, which leads to increased complexity and maintenance requirements.

Application Layer

The application layer provides end users with the services and applications running on the hybrid cloud that use the underlying cloud resources to perform a variety of tasks.

Scalability on this layer is commonly achieved through a microservices architecture, using the capabilities provided by Kubernetes on the platform layer. In turn, Kubernetes enables using stateless applications, which allows you to add or remove pods in response to demand without affecting performance or user experience.

In addition to scalability, the cloud-agnostic nature of containers in microservices architecture enables interoperability, compatibility and seamless communication and data exchange between applications and services regardless of the cloud environment they reside in—key for hybrid cloud setups.

Keep in mind that the application layer alone cannot ensure efficient management of fluctuating workloads or high availability of applications. This layer's performance is directly influenced by the design choices made on the infrastructure and platform layers. Essentially, its effectiveness is based on the capabilities built into those layers.

That said, let's go over typical options for apps and services on this layer.

Build Your Own Hybrid Cloud: Application Layer

The applications and services running on the application layer are closely tied to your specific project. For instance, a global news site will not need to deploy the same apps as a financial institution. With this in mind, let's review some services you may need:

• Web/application servers handle HTTP/HTTPS requests and serve web content to users. You have a lot of options here, including Apache, Nginx and lighttpd.
• Application servers execute and manage business logic. For example, you can use an app like WordPress as a content management system or as a storefront on an e-commerce site.
• An API gateway acts as a single entry point for all client requests and provides routing for API calls. Projects like Express Gateway offer such functionality, allowing private service endpoints to communicate with public API endpoints.
• Application performance monitoring (APM) tools provide visibility into the performance of applications to help you identify and diagnose complex issues to ensure an optimal user experience. For instance, Nagios is a tool that offers comprehensive infrastructure monitoring and network analysis in addition to APM. 
• Databases store and manage data for applications to ensure efficient access and retrieval, regardless of the underlying cloud infrastructure. Similar to web servers, you have many alternatives depending on your use case. Popular picks include MySQL, PostgreSQL, Redis and MongoDB.
• Messaging and event streaming services enable real-time data processing between distributed application components and support decoupled architectures for scalability and reliability. In this category, you'll find a variety of options that depend on the specific requirements of your project. Some options include Apache Kafka and Apache Spark.

This list could go on and include things like AI-driven analytical prediction services and security frameworks that handle authentication and authorization. All the apps and services that your project requires reside on this layer.

Importance of Flexibility in Your Hybrid Cloud Architecture

Including an infrastructure monitoring tool like Nagios at the application layer may have confused you. Shouldn't it be part of the platform layer?

The truth is that the line that separates the different layers is sometimes very thin. Your use case may require a certain functionality on the upper layers, in which case you should focus on implementing it on the infrastructure or platform layer instead of the application layer. A good example is load balancing.

At the infrastructure layer, load balancers can be used for traffic distribution across cloud regions to optimize resource utilization and fault tolerance. Alternatively, you can integrate load balancers within specific applications at the application layer to manage incoming traffic and improve availability.

As you can see, nothing is set in stone when it comes to designing a hybrid cloud; the ultimate goal is to fulfill your specific needs. That's why it's so important to use infrastructure that offers you the control and flexibility necessary to implement any functionality on the layer that you consider appropriate. That's exactly what Equinix Dedicated Cloud offers you: the flexibility to build the hybrid cloud you need. Get in control of your cloud journey with Equinix today.