-----------------
Networking applications are of three types - Management applications,
-Control plane applications and data plane applications. Management
+Control plane applications and data plane applications. Management
and control plane applications are similar to Enterprise applications,
but data plane applications different in following aspects:
New Proposal
------------
-A new plugin addressing the below requirements,
-
-- For networking workloads as well typical application workloads
+A new plugin addresses the below requirements, for networking
+workloads as well typical application workloads
- Multi-interface support
- Multi-IP address support
- Dynamic creation of virtual networks
and L3 overlays and security groups. Services such as DHCP are also
desirable features. Just like OVS, OVN’s design goal is to have a
production quality implementation that can operate at significant
-scale.
+scale.
+
+**OVN4NFVK8s Plugin development**
+
+ovn-kubernetes_ plugin is part of OVN project which provides OVN
+integration with Kubernetes but doesn't address the requirements
+as given above. To meet those requirements like multiple interfaces,
+IPs, dynamic creation of virtual networks, etc., OVN4NFVK8s plugin is
+created. It assumes that it will be used in conjuction with Multus_
+or other similar CNI which allows for the co-existance of multiple
+CNI plugins in runtime. This plugin assumes that the first interface
+in a Pod is provided by some other Plugin/CNI like Flannel or even
+OVN-Kubernetes. It is only responsible to add multiple interfaces
+based on the Pod annotations. The code is based on ovn-kubernetes_.
+
+
+.. note::
+
+ This plugin is currently tested to work with Multus and Flannel
+ providing the first network interface.
+
+To meet the requirement of multiple interfaces and IP's per pod,
+a Pod annotation like below is required when working with Multus:
+
+
+.. code-block:: yaml
+
+
+ annotations:
+ k8s.v1.cni.cncf.io/networks: '[{ "name": "ovn-networkobj"}]'
+ ovnNetwork '[
+ { "name": <name of OVN Logical Switch>, "interfaceRequest": "eth1" },
+ { "name": <name of OVN Logical Switch>, "interfaceRequest": "eth2" }
+ ]'
+
+Based on these annotations watcher service in OVN4NFVK8s plugin assumes
+logical switch is already present. Dynamic IP addresses are assigned
+(static IP's also supported) and annotations are updated.
+
+When the Pod is initialized on a node, OVN4NFVK8s CNI creates multiple
+interfaces and assigns IP addresses for the pod based on the annotations.
+
+**Multus Configuration**
+Multus CRD definition for OVN:
+
+.. code-block:: yaml
+
+ apiVersion: "k8s.cni.cncf.io/v1"
+ kind: NetworkAttachmentDefinition
+ metadata:
+ name: ovn-networkobj
+ spec:
+ config: '{
+ "cniVersion": "0.3.1",
+ "name": "ovn4nfv-k8s-plugin",
+ "type": "ovn4nfvk8s-cni"
+ }'
+
+Please refer to Multus_ for details about how this configuration is used
+
+CNI configuration file for Multus with Flannel:
+
+.. code-block:: yaml
+
+ {
+ "type": "multus",
+ "name": "multus-cni",
+ "cniVersion": "0.3.1",
+ "kubeconfig": "/etc/kubernetes/admin.conf",
+ "delegates": [
+ {
+ "type": "flannel",
+ "cniVersion": "0.3.1",
+ "masterplugin": true,
+ "delegate": {
+ "isDefaultGateway": false
+ }
+ }
+ ]
+ }
-**K8S-OVN4NFV Plugin development**
+Refer Kubernetes_ documentation for the order in which CNI configurations
+are applied.
-Some code and ideas are being taken from ovn-kubernetes_ plugin
-work that was done as part of OVN project. Due to good number of
-changes, it is a new plugin with its own code base. This plugin
-assumes that the first interface in a Pod is provided by some other
-Plugin/CNI like Flannel or even OVN-Kubernetes and this plugin is
-only responsible to add multiple interfaces based on the Pod
-annotations. This plugin is currently tested to work with Multus as
-CNI and Flannel as first interface.
-Its functionality is divided into to following:
+**Build**
-- Initialization:
+For building the project:
- - Register itself as watcher to K8S API Server to receive POD events
- and service events.
- - Creates a distributed router
- - Creates gateway
- - Creates a logical switch to connect distributed router with
- Gateway.
- - Creates a subnet between distributed router & Gateway.
- - Assigns first two IP addresses of the subnet to router and
- Gateway.
- - Created router port and gateway port as part of assigning IP
- address and MAC addresses.
+.. code-block:: bash
-- Watcher:
+ cd ovn4nfv-k8s-plugin
+ make
- - Upon POD bring up event
- - Checks the annotations specific to OVN.
- - For each network on which POD is going to be brought up
- - Validates whether the logical switch is already present. If not,
- it is considered as error.
- - If IP address and MAC addresses are not static, it asks OVN to
- assign IP and MAC address.
- - Collects all IP addresses/MAC addresses assigned. Puts them as
- annotations (dynamic information) for that POD.
+This will output two files ovn4nfvk8s and ovn4nfvk8s-cni which are the plugin
+ and CNI binaries respectively.
- - Upon POD deletion event
+ovn4nfvk8s plugin requires some configuration at start up.
- - Returns the IP address and MAC address back to OVN pool.
+Example configuration file (default location/etc/openvswitch/ovn4nfv_k8s.conf)
-- OVN CNI
+.. code-block:: yaml
-This is present in every minion node. CNI is expected to be called
-once for all OVN networks either Kubelet directly or via Multus.
+ [logging]
+ loglevel=5
+ logfile=/var/log/openvswitch/ovn4k8s.log
- - Add:
+ [cni]
+ conf-dir=/etc/cni/net.d
+ plugin=ovn4nfvk8s-cni
- - Wait for annotations to be filled up by the watcher. From
- annotations, it knows set of IP Address, MAC address and Routes
- to be added.
- - Using network APIs for each element in the set:
- - Creates veth pair.
- - Assigns the IP address and MAC address to one end of veth pair.
- Other end veth pair is assigned to br-int.
- - Creates routes based on the route list provided in annotations.
+ [kubernetes]
+ kubeconfig=/etc/kubernetes/admin.conf
- - If isDefaultRoute is set in annotations, it creates default route
- using this veth.
- - Delete
- - Removes veth pair.
- - Removes routes.
**Figure**
+--------------------+
- Complete Architecture can be found in ovn-kubernetes documentation at github
**References**
-.. _ovn-kubernetes: https://wiki.opnfv.org/display/OV/K8S+OVN+NFV+Plugin
+.. _ovn-kubernetes: https://github.com/openvswitch/ovn-kubernetes
+.. _Multus: https://github.com/intel/multus-cni
+.. _Kubernetes: https://kubernetes.io/docs/concepts/extend-kubernetes/compute-storage-net/network-plugins/
**Authors/Contributors**
Code Review / ovn4nfv-k8s-plugin.git / commitdiff