Overlay Networking

Overlay Networking An architecture diagram generated by Archify. Container A · IP: 10.0.0.2 · Host A Container A IP: 10.0.0.2 Overlay Network · 10.0.0.0/24 · Host A Overlay Network 10.0.0.0/24 eth0 · 192.168.1.10 · Host A eth0 192.168.1.10 Container B · IP: 10.0.0.3 · Host B Container B IP: 10.0.0.3 Overlay Network · 10.0.0.0/24 · Host B Overlay Network 10.0.0.0/24 eth0 · 192.168.1.11 · Host B eth0 192.168.1.11 encapsulate VXLAN tunnel (UDP 4789) decapsulate Host A Host B Legend Container Overlay network Physical interface

Overlay networking traits

  • • Connects containers running across multiple hosts
  • • Uses encapsulation protocols such as VXLAN and GENEVE
  • • Suits large clusters; supported by Cilium, Calico, Flannel and others

How it works

  • • Encapsulation: the original packet is wrapped in new headers
  • • Tunneling: sent across the physical network to the destination host
  • • After decapsulation the original packet is delivered to the target container