K8s in the Datacenter - Integrating with Preexisting Bare Metal Environments

Explore the challenges and solutions of integrating Kubernetes into existing bare metal datacenter environments in this conference talk. Dive into adapting Kubernetes components like kube-proxy and Calico networking project for pure L3 ECMP fabric configurations. Learn about network overlay considerations, diagnosing Linux networking issues using tools such as ebpf, ftrace, tcpdump, and conntrack, and providing network connectivity with and without overlays. Gain insights into running multiple BIRD instances, addressing iptables MASQUERADE issues, and advanced network kernel debugging techniques for seamless K8s integration in diverse datacenter architectures.

Intro
Overview
KBs Networking Model - Pods are schedulable units of work
Overlay Networks
Choosing Flat vs. Overlay: Overlays
Choosing Flat vs. Overlay: Flat
Other Considerations
Issue #1: Running Multiple BIRD Instances
Issue #2: iptables Masquerade
Addressing MASQUERADE: Kernel Bug?
Network Debugging: Going Deeper
Network (Kernel) Debugging: Even Deeper