5장. Creating Multus networks

To utilize Multus, an already working cluster with the correct networking configuration is required, see Requirements for Multus configuration. The newly created NetworkAttachmentDefinition (NAD) can be selected during the Storage Cluster installation. This is the reason they must be created before the Storage Cluster.

You can select the newly created NetworkAttachmentDefinition (NAD) during the Storage Cluster installation. This is the reason you must create the NAD before you create the Storage Cluster.

As detailed in the Planning Guide, the Multus networks you create depend on the number of available network interfaces you have for OpenShift Data Foundation traffic. It is possible to separate all of the storage traffic onto one of the two interfaces (one interface used for default OpenShift SDN) or to further segregate storage traffic into client storage traffic (public) and storage replication traffic (private or cluster).

The following is an example NetworkAttachmentDefinition for all the storage traffic, public and cluster, on the same interface. It requires one additional interface on all schedulable nodes (OpenShift default SDN on separate network interface):

apiVersion: "k8s.cni.cncf.io/v1"
kind: NetworkAttachmentDefinition
metadata:
 name: ceph-multus-net
 namespace: openshift-storage
spec:
 config: '{
     "cniVersion": "0.3.1",
     "type": "macvlan",
     "master": "eth0",
     "mode": "bridge",
     "ipam": {
       "type": "whereabouts",
       "range": "192.168.200.0/24",
       "routes": [
         {"dst": "NODE_IP_CIDR"}
       ]
     }
   }'

The following is an example NetworkAttachmentDefinition for storage traffic on separate Multus networks, public, for client storage traffic, and cluster, for replication traffic. It requires two additional interfaces on OpenShift nodes hosting object storage device (OSD) pods and one additional interface on all other schedulable nodes (OpenShift default SDN on separate network interface):

apiVersion: "k8s.cni.cncf.io/v1"
kind: NetworkAttachmentDefinition
metadata:
  name: ocs-public
  namespace: openshift-storage
spec:
  config: '{
  	"cniVersion": "0.3.1",
  	"type": "macvlan",
  	"master": "ens2",
  	"mode": "bridge",
  	"ipam": {
    	    "type": "whereabouts",
    	    "range": "192.168.1.0/24"
  	}
  }'

Example NetworkAttachmentDefinition:

apiVersion: "k8s.cni.cncf.io/v1"
kind: NetworkAttachmentDefinition
metadata:
  name: ocs-cluster
  namespace: openshift-storage
spec:
  config: '{
  	"cniVersion": "0.3.1",
  	"type": "macvlan",
  	"master": "ens3",
  	"mode": "bridge",
  	"ipam": {
    	    "type": "whereabouts",
    	    "range": "192.168.2.0/24"
  	}
  }'