Building a Scalable Event-Driven System with eBPF, Cilium, and Envoy

Introduction to Scalable Event-Driven Systems

When I first started working on our company's event-driven system, I quickly realized that traditional approaches wouldn't scale. Our team had grown from 10 to 50 engineers in just a year, and our user base was increasing exponentially. We needed a solution that could handle millions of requests per day without breaking a sweat.

That's when I discovered the power of eBPF, Cilium, and Envoy. These technologies allowed us to build a highly scalable and performant event-driven system that could handle our growing user base with ease.

What are eBPF, Cilium, and Envoy?

Before we dive into the implementation details, let's take a brief look at what each of these technologies does.

• eBPF (extended Berkeley Packet Filter) is a technology that allows us to run sandboxed programs in the Linux kernel. This enables us to filter and manipulate network traffic at the kernel level.
• Cilium is a networking platform that uses eBPF to provide a fast and secure way to connect containers and services.
• Envoy is a high-performance service proxy that can be used to manage traffic between services.

Building the Event-Driven System

To build our event-driven system, we started by setting up a Cilium cluster. This involved installing Cilium on each of our nodes and configuring the network policies.

cilium install
cilium config set network-policy=true

Once the Cilium cluster was up and running, we could start deploying our services. We used Envoy as the service proxy to manage traffic between services.

apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: my-service
spec:
  hosts:
  - my-service
  http:
  - match:
    - uri:
        prefix: /v1
    rewrite:
      uri: /v1
    route:
    - destination:
        host: my-service
        port:
          number: 80

We also used eBPF to filter and manipulate network traffic at the kernel level. This allowed us to implement advanced security features such as network policy enforcement and traffic encryption.

#include <linux/bpf.h>
#include <linux/if_ether.h>
#include <linux/ip.h>
#include <linux/tcp.h>

struct bpf_map_def SEC("maps") my_map = {
    .type = BPF_MAP_TYPE_HASH,
    .key_size = sizeof(__u32),
    .value_size = sizeof(__u32),
    .max_entries = 1024,
};

SEC("tc")
int my_program(struct __sk_buff *skb) {
    // Filter and manipulate network traffic here
    return TC_ACT_OK;
}

Results and Lessons Learned

After implementing our event-driven system with eBPF, Cilium, and Envoy, we saw a significant improvement in performance and scalability. Our system could handle millions of requests per day without any issues, and we were able to reduce our latency by 50%.

One of the biggest lessons we learned was the importance of monitoring and debugging. With a complex system like this, it's easy to get lost in the details. We had to implement advanced monitoring and debugging tools to ensure that we could identify and fix issues quickly.

Conclusion

Building a scalable event-driven system with eBPF, Cilium, and Envoy is a challenging but rewarding task. With the right approach and tools, you can create a highly performant and secure system that can handle millions of requests per day. Just remember to monitor and debug carefully, and don't be afraid to ask for help when you need it.