eBPF in Kubernetes: The Technology Behind Modern Networking

eBPF (Extended Berkeley Packet Filter) is revolutionizing how we handle networking, security, and observability in Kubernetes by running code in the kernel space efficiently.

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.

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References:

• eBPF.io
• Cilium eBPF