Managing a multitenant server infrastructure presents unique challenges. Over time, we realized that our existing setup, which relied on multiple individually managed servers (with new ones added piecemeal), was becoming challenging to scale, maintain, and optimize. So we decided to reinforce and improve.
The Challenges
- Scalability: As our user base grew, manually scaling servers and applications became a cumbersome process. We needed a solution that could handle varying loads dynamically and efficiently.
- Resource Utilization: With individually managed servers, it was challenging to distribute workloads optimally. This led to some servers being overutilized while others were underutilized, resulting in inefficient resource use.
- Deployment Inconsistency: Differences in Moodle environments made validating consistent behaviour across applications a recurring headache.
- Maintenance Overhead: Managing and updating multiple servers individually was time-consuming and error-prone. The increasing complexity made it hard to keep up with maintenance tasks.
- Fault Tolerance: The lack of failover mechanisms can lead to increased downtime during server failures.
Enter Kubernetes
Kubernetes (K8s) is an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications. Addressing the key pain points we were having with our previous infrastructure.
Fixing Scalability Issues
By adding a Kubernetes control plane on top of our discrete servers, we now have the ability to pool our resources together. As more sites are created, we can match the demand by adding more servers to the cluster, allowing us to respond faster to increased client demand.
Using the Control Plane to distribute resources
Following the theme of using the control plane to fix our issues, in the event that one site starts requiring more resources, we can have Kubernetes move the sites that don’t require as much power to a different node in the cluster, allowing the in-demand site to maintain a highly responsive experience for the end user.
This means clients should have a quality experience no matter the site load.
Consistent Deployments
By containerizing our applications, we ensure they run consistently across different environments. Kubernetes uses declarative configuration to manage these deployments, reducing the chances of environment-specific issues—which means fewer client-specific issues.
Simplified Maintenance
With Kubernetes, we can centrally manage our containers and applications. This greatly simplifies maintenance tasks and allows us to roll out updates and patches more smoothly. Which means fewer errors are piling up on user sites.
Enhanced Fault Tolerance
Kubernetes comes with built-in self-healing capabilities. It can automatically restart failed containers, reschedule them on healthy nodes, and replicate services to ensure high availability. This significantly reduces downtime and improves the resilience of our infrastructure. This means that when issues do occur, users should see them less.
The Benefits We See
- Better Resource Efficiency: Kubernetes’ efficient workload distribution has led to better resource utilization, reducing our operational costs.
- Faster Deployments: With our new CI/CD pipelines, we can deploy updates and new features more quickly and reliably.
- Reduced Downtime: Automated failover and recovery mechanisms have significantly reduced downtime, ensuring our services are always available to users.
- Simplified Management: Centralized management and maintenance have freed up time and resources, allowing us to focus more on innovation and less on routine tasks.
- No Vendor lock-in: Kubernetes provides an experience very similar to a public cloud. As long as you know how to operate it, you can provide an experience incredibly similar to the AWS, Azure, or GCP experience, complete with load balancers, API gateways, and storage tiers. All of this is backed by a world-class API that we can expand ourselves via the controller paradigm if we so desire.
This is to say that Kubernetes has been a huge boon to our system’s reliability. It has allowed us to streamline the deployment of new clients. Turning it from a multi-hour (or even day!) process involving dozens of manual changes to a task that can be triggered by a developer and completed in a few minutes. It has addressed the key challenges we faced with our previous setup, providing a scalable, efficient, and resilient solution that positions us well for future growth. All these reasons and more are why we chose Kubernetes as our hosting platform.
