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README.md

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+# docker-net-dhcp
+`docker-net-dhcp` is a Docker plugin providing a network driver which allocates IP addresses (IPv4 and optionally IPv6)
+via an existing DHCP server (e.g. your router).
+
+When configured correctly, this allows you to spin up a container (e.g. `docker run ...` or `docker-compose up ...`) and
+access it on your network as if it was any other machine!
+
+# Usage
+## Installation
+```
+$ docker plugin install devplayer0/net-dhcp
+Plugin "devplayer0/net-dhcp" is requesting the following privileges:
+ - network: [host]
+ - host pid namespace: [true]
+ - mount: [/var/run/docker.sock]
+ - capabilities: [CAP_NET_ADMIN CAP_SYS_ADMIN]
+Do you grant the above permissions? [y/N] y
+latest: Pulling from devplayer0/net-dhcp
+<some id>: Download complete 
+Digest: sha256:<some hash>
+Status: Downloaded newer image for devplayer0/net-dhcp:latest
+Installed plugin devplayer0/net-dhcp
+$
+```
+
+## Network creation
+In order to create a Docker network using `net-dhcp`, you'll need a pre-configured bridge interface on the host. How you
+set this up will depend on your system, but the following (manual) instructions should work on most Linux distros:
+```
+# Create the bridge
+$ sudo ip link add my-bridge type bridge
+$ sudo ip link set my-bridge up
+
+# Assuming 'eth0' is connected to your LAN (where the DHCP server is)
+$ sudo ip link set eth0 up
+# Attach your network card to the bridge
+$ sudo ip link set eth0 master my-bridge
+
+# Get an IP for the host (will go out to the DHCP server since eth0 is attached to the bridge)
+$ sudo dhcpcd my-bridge
+```
+
+Once the bridge is ready, you can create the network:
+```
+$ docker network create -d devplayer0/net-dhcp:latest --ipam-driver null -o bridge=my-bridge my-dhcp-net
+<some network id>
+$
+
+# With IPv6 enabled
+# Although `docker network create` has a `--ipv6` flag, it doesn't work with the null IPAM driver
+$ docker network create -d devplayer0/net-dhcp:latest --ipam-driver null -o bridge=test -o ipv6=true my-dhcp-net
+<some network id>
+$
+```
+_Note: The `null` IPAM driver **must** be used, or else Docker will try to allocate IP addresses from its choice of
+subnet - this can cause IP conflicts since the bridge is connected to your local network!_
+
+## Container creation
+Once you've created a network, you can create some containers:
+```
+$ docker run --rm -ti --network my-dhcp-net alpine
+/ # ip address show
+1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1000
+    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
+    inet 127.0.0.1/8 scope host lo
+       valid_lft forever preferred_lft forever
+159: my-bridge0@if160: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP qlen 1000
+    link/ether 86:41:68:f8:85:b9 brd ff:ff:ff:ff:ff:ff
+    inet 10.255.0.246/24 brd 10.255.0.255 scope global test0
+       valid_lft forever preferred_lft forever
+/ # ip route show
+default via 10.255.0.123 dev my-bridge0 
+10.255.0.0/24 dev my-bridge0 scope link  src 10.255.0.246 
+/ #
+```
+Note:
+ - It will take a bit longer than usual for the container to start, as a DHCP lease needs to be obtained before creating it
+ - Once created, a persistent DHCP client will renew the DHCP lease (and then update the default gateway in the
+ container) when necessary - **this client runs separately from the container**