Understanding Docker Networking#
The mental model#
Linux networking is just C code in the kernel simulating switches and routers in memory. It’s simply the system passing a packets in RAM from one function to the next. Once you accept that, everything becomes much easier to follow.
Network Modes#
Docker has seven network drivers. Each controls how containers reach the host, each other, and your LAN.
| Driver | Summary |
|---|---|
| bridge | Default. Private virtual switch with NAT to the host. |
| host | Shares the host network stack. No isolation. |
| none | Loopback only. No network access. |
| macvlan | Each container gets its own MAC and LAN IP. |
| ipvlan L2 | Own LAN IP, shared parent MAC. |
| ipvlan L3 | Host routes container subnets. No broadcast. |
| overlay | Multi-host networking over VXLAN. Requires Swarm. |