eBPF in Kubernetes: The Technology Behind Modern Networking

Understanding eBPF

eBPF programs run in a sandboxed virtual machine within the Linux kernel, processing events without kernel modifications.

// Simple eBPF program example
SEC("xdp")
int xdp_drop_all(struct xdp_md *ctx) {
    return XDP_DROP;  // Drop all packets
}

eBPF Use Cases in Kubernetes

• Networking: Replace iptables with faster eBPF rules
• Security: Syscall filtering, runtime security
• Observability: Kernel-level tracing
• Load Balancing: Efficient service routing

Kubernetes Components Using eBPF

• Cilium CNI
• Calico eBPF mode
• Falco runtime security
• Pixie observability

Performance Benefits

# Compare iptables vs eBPF
# iptables: O(n) rule matching
# eBPF: O(1) hash-based lookup

Summary

eBPF enables next-generation Kubernetes infrastructure with improved performance, security, and observability at the kernel level.