Cilium
Cilium is an open-source networking, observability, and security solution for Kubernetes, leveraging eBPF technology for high-performance networking and advanced network policies.
| Category | Container & Kubernetes Security |
|---|---|
| Last Commit | 1 year ago |
| This page updated | a month ago |
| Pricing Details | Free and open-source. |
| Target Audience | Kubernetes administrators, DevOps engineers, and cloud-native application developers. |
Cilium addresses the complex networking, observability, and security challenges in Kubernetes environments through its eBPF-based architecture. This approach leverages the extended Berkeley Packet Filter (eBPF) technology to provide high-performance networking, advanced network policies, and enhanced security.
At its core, Cilium integrates with the Container Network Interface (CNI) to offer features such as high-performance networking, layer 4 load balancing, and service mesh capabilities. It extends the Kubernetes NetworkPolicy API to support layer 7 (L7) network policies, allowing for more granular control over ingress and egress traffic, including port ranges and specific endpoint matching.
Operationally, Cilium's eBPF implementation enables identity-aware network flow logs and advanced network protocol visibility, which are crucial for monitoring and troubleshooting in large-scale Kubernetes deployments. The CiliumClusterwideNetworkPolicy allows for inter-node traffic control, facilitating the enforcement of policies across the entire cluster rather than just within namespaces.
Key operational considerations include the need for careful policy configuration to avoid overly restrictive or permissive settings. For instance, the "everything is forbidden by default" rule can be implemented using Cilium's policy enforcement modes, requiring a detailed specification of allowed traffic flows. Additionally, while Cilium offers robust features, its performance and stability can be affected by the complexity of the policies and the scale of the cluster. For example, features like the Local Redirect Policy and EndpointSlice CRD support are still in beta and require monitoring for stability before widespread adoption.
Technically, Cilium's use of eBPF allows for low-overhead packet processing and filtering, which is essential for maintaining high network performance. However, this also means that administrators need to be familiar with eBPF and its limitations to fully leverage Cilium's capabilities. The integration with Kubernetes APIs and CRDs ensures seamless management and monitoring, but it also introduces dependencies on the underlying Kubernetes infrastructure.