Matthias Radestock
0635ed1854
* highlight the need for `weave expose` in CNI/k8s Fixes #2405 * Extend error message * rearranged the sentences weave launch <peer hosts> seems a bit orphaned here maybe include the weave connect command as well, since it's being mentioned.
80 lines
2.8 KiB
Markdown
80 lines
2.8 KiB
Markdown
---
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title: Integrating Kubernetes via the CNI Plugin
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menu_order: 65
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---
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CNI, the [_Container Network Interface_](https://github.com/appc/cni#cni---the-container-network-interface),
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is a proposed standard for configuring network interfaces for Linux
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application containers. CNI is supported by
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[Kubernetes](http://kubernetes.io/), an open source container cluster
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manager built by Google.
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###Installing the Weave Net CNI plugin
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If your machine has the directories normally used to host CNI plugins,
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then the Weave Net CNI plugin is installed when you run `weave setup`.
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To create those directories, run (as root):
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mkdir -p /opt/cni/bin
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mkdir -p /etc/cni/net.d
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Then run:
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weave setup
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###Launching Weave Net
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To create a network that spans multiple hosts, the Weave peers must be connected to each other.
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This is accomplished by specifying the other hosts during `weave launch` or via
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[`weave connect`](/site/using-weave/finding-adding-hosts-dynamically.md).
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See [Creating Peer Connections Between Hosts](/site/using-weave.md#peer-connections)
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for a discussion on peer connections.
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weave launch <peer hosts>
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Next, assign an IP address to the Weave bridge and [enable access to containers from the host](/site/using-weave/host-network-integration.md),
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which is required by Kubernetes, by running the following:
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weave expose
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###Configuring Kubernetes to use the CNI Plugin
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After you've launched Weave and peered your hosts, you can configure
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Kubernetes to use Weave, by adding the following options to the
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`kubelet` command:
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--network-plugin=cni --network-plugin-dir=/etc/cni/net.d
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See the [`kubelet` documentation](http://kubernetes.io/v1.1/docs/admin/kubelet.html)
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for more details.
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Now, whenever Kubernetes starts a pod, it will be attached to the Weave network.
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###Using the CNI network configuration file
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All CNI plugins are configured by a JSON file in the directory
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`/etc/cni/net.d/`. `weave setup` installs a minimal configuration
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file named `10-weave.conf`, which you can alter to suit your needs.
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See the [CNI Spec](https://github.com/appc/cni/blob/master/SPEC.md#network-configuration)
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for details on the format and contents of this file.
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By default, the Weave CNI plugin adds a default route out via the Weave bridge, so your containers can access resources on the internet. If you do not want this, add a section to the config file that specifies no routes:
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"ipam": {
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"routes": [ ]
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}
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The following other fields in the spec are supported:
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- `ipam / type` - default is to use Weave's own IPAM
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- `ipam / subnet` - default is to use Weave's IPAM default subnet
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- `ipam / gateway` - default is to use the Weave bridge IP address (allocated by `weave expose`)
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###Caveats
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- The Weave Net router container must be running for CNI to allocate addresses
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- The CNI plugin does not add entries to weaveDNS.
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