diff --git a/host-local.md b/host-local.md index 00c1e84c..073e369a 100644 --- a/host-local.md +++ b/host-local.md @@ -1,12 +1,17 @@ -# host-local plugin +# host-local IP address management plugin + +host-local IPAM allocates IPv4 and IPv6 addresses out of a specified address range. Optionally, +it can include a DNS configuration from a `resolv.conf` file on the host. ## Overview host-local IPAM plugin allocates IPv4 addresses out of a specified address range. It stores the state locally on the host filesystem, therefore ensuring uniqueness of IP addresses on a single host. -## Example configuration -``` +## Example configurations + +IPv4: +```json { "ipam": { "type": "host-local", @@ -17,11 +22,44 @@ It stores the state locally on the host filesystem, therefore ensuring uniquenes "routes": [ { "dst": "0.0.0.0/0" }, { "dst": "192.168.0.0/16", "gw": "10.10.5.1" } - ] + ], + "dataDir": "/var/my-orchestrator/container-ipam-state" } } ``` +IPv6: +```json +{ + "ipam": { + "type": "host-local", + "subnet": "3ffe:ffff:0:01ff::/64", + "rangeStart": "3ffe:ffff:0:01ff::0010", + "rangeEnd": "3ffe:ffff:0:01ff::0020", + "routes": [ + { "dst": "3ffe:ffff:0:01ff::1/64" } + ], + "resolvConf": "/etc/resolv.conf" + } +} +``` + +We can test it out on the command-line: + +```bash +$ export CNI_COMMAND=ADD +$ export CNI_CONTAINERID=f81d4fae-7dec-11d0-a765-00a0c91e6bf6 +$ echo '{ "name": "default", "ipam": { "type": "host-local", "subnet": "203.0.113.0/24" } }' | ./host-local +``` + +```json +{ + "ip4": { + "ip": "203.0.113.1/24" + } +} +``` + ## Network configuration reference * `type` (string, required): "host-local". @@ -31,6 +69,8 @@ It stores the state locally on the host filesystem, therefore ensuring uniquenes * `gateway` (string, optional): IP inside of "subnet" to designate as the gateway. Defaults to ".1" IP inside of the "subnet" block. * `routes` (string, optional): list of routes to add to the container namespace. Each route is a dictionary with "dst" and optional "gw" fields. If "gw" is omitted, value of "gateway" will be used. * `resolvConf` (string, optional): Path to a `resolv.conf` on the host to parse and return as the DNS configuration +* `dataDir` (string, optional): Path to a directory to use for maintaining state, e.g. which IPs have been allocated to which containers + ## Supported arguments The following [CNI_ARGS](https://github.com/containernetworking/cni/blob/master/SPEC.md#parameters) are supported: @@ -39,4 +79,4 @@ The following [CNI_ARGS](https://github.com/containernetworking/cni/blob/master/ ## Files -Allocated IP addresses are stored as files in /var/lib/cni/networks/$NETWORK_NAME. +Allocated IP addresses are stored as files in `/var/lib/cni/networks/$NETWORK_NAME`. The prefix can be customized with the `dataDir` option listed above.