11.2. Updating node network configuration
You can update the node network configuration, such as adding or removing interfaces from nodes, by applying NodeNetworkConfigurationPolicy
manifests to the cluster.
11.2.1. About nmstate
OpenShift Virtualization uses nmstate
to report on and configure the state of the node network. This makes it possible to modify network policy configuration, such as by creating a Linux bridge on all nodes, by applying a single configuration manifest to the cluster.
Node networking is monitored and updated by the following objects:
NodeNetworkState
- Reports the state of the network on that node.
NodeNetworkConfigurationPolicy
-
Describes the requested network configuration on nodes. You update the node network configuration, including adding and removing interfaces, by applying a
NodeNetworkConfigurationPolicy
manifest to the cluster. NodeNetworkConfigurationEnactment
- Reports the network policies enacted upon each node.
OpenShift Virtualization supports the use of the following nmstate interface types:
- Linux Bridge
- VLAN
- Bond
- Ethernet
11.2.2. Creating an interface on nodes
Create an interface on nodes in the cluster by applying a NodeNetworkConfigurationPolicy
manifest to the cluster. The manifest details the requested configuration for the interface.
By default, the manifest applies to all nodes in the cluster. To add the interface to specific nodes, add the spec: nodeSelector
parameter and the appropriate <key>:<value>
for your node selector.
Procedure
Create the
NodeNetworkConfigurationPolicy
manifest. The following example configures a Linux bridge on all worker nodes:apiVersion: nmstate.io/v1alpha1 kind: NodeNetworkConfigurationPolicy metadata: name: <br1-eth1-policy> 1 spec: nodeSelector: 2 node-role.kubernetes.io/worker: "" 3 desiredState: interfaces: - name: br1 description: Linux bridge with eth1 as a port 4 type: linux-bridge state: up ipv4: dhcp: true enabled: true bridge: options: stp: enabled: false port: - name: eth1
Create the Policy:
$ oc apply -f <br1-eth1-policy.yaml> 1
- 1
- File name of the Policy manifest.
Additional resources
11.2.3. Confirming Policy updates on nodes
A NodeNetworkConfigurationPolicy
manifest describes your requested network configuration for nodes in the cluster. The Policy object includes your requestd network configuration and the status of execution of the Policy on the cluster as a whole.
When you apply a Policy, a NodeNetworkConfigurationEnactment
is created for every node in the cluster. The Enactment is a read-only object that represents the status of execution of the Policy on that node. If the Policy fails to be applied on the node, the Enactment for that node includes a traceback for troubleshooting.
Procedure
To confirm that a Policy has been applied to the cluster, list the Policies and their status:
$ oc get nncp
Optional: If a Policy is taking longer than expected to successfully configure, you can inspect the requested state and status conditions of a particular Policy:
$ oc get nncp <policy> -o yaml
Optional: If a policy is taking longer than expected to successfully configure on all nodes, you can list the status of the Enactments on the cluster:
$ oc get nnce
Optional: To view the configuration of a particular Enactment, including any error reporting for a failed configuration:
$ oc get nnce <node>.<policy> -o yaml
11.2.4. Removing an interface from nodes
Remove an interface from nodes by editing the NodeNetworkConfigurationPolicy
object and set the state
of the interface to absent
.
Deleting the Policy that added an interface does not change the configuration of the network policy on the node. Although a NodeNetworkConfigurationPolicy
is an object in the cluster, it only represents the requested configuration.
Similarly, removing an interface does not delete the Policy.
Procedure
Update the
NodeNetworkConfigurationPolicy
manifest used to create the interface. The following example removes a Linux bridge:apiVersion: nmstate.io/v1alpha1 kind: NodeNetworkConfigurationPolicy metadata: name: <br1-eth1-policy> 1 spec: nodeSelector: 2 node-role.kubernetes.io/worker: "" 3 desiredState: interfaces: - name: br1 type: linux-bridge state: absent 4
Update the Policy on the node and remove the interface:
$ oc apply -f <br1-eth1-policy.yaml> 1
- 1
- File name of the Policy manifest.
11.2.5. Restoring node network configuration after removing an interface
Removing an interface from a node does not automatically restore the node network configuration to a previous state. After you remove an interface, any of the node NICs throughout the cluster that were previously attached or subordinate to the interface are placed in a down
state. Restore the NICs by applying a new NodeNetworkConfigurationPolicy
manifest to the cluster.
Procedure
Create a
NodeNetworkConfigurationPolicy
manifest that specifies the NIC and the desired state ofup
:apiVersion: nmstate.io/v1alpha1 kind: NodeNetworkConfigurationPolicy metadata: name: eth1 spec: desiredState: interfaces: - name: eth1 type: ethernet state: up ipv4: dhcp: true enabled: true
Apply the manifest to the cluster:
$ oc apply -f <eth1.yaml> 1
- 1
- File name of the Policy manifest.
11.2.6. Example Policy configurations for different interfaces
11.2.6.1. Example: Linux bridge interface NodeNetworkConfigurationPolicy
Create a Linux bridge interface on nodes in the cluster by applying a NodeNetworkConfigurationPolicy
manifest to the cluster.
The following YAML file is an example of a manifest for a Linux bridge interface. It includes samples values that you must replace with your own information.
apiVersion: nmstate.io/v1alpha1 kind: NodeNetworkConfigurationPolicy metadata: name: br1-eth1-policy 1 spec: nodeSelector: 2 kubernetes.io/hostname: <node01> 3 desiredState: interfaces: - name: br1 4 description: Linux bridge with eth1 as a port 5 type: linux-bridge 6 state: up 7 ipv4: dhcp: true 8 enabled: true 9 bridge: options: stp: enabled: false 10 port: - name: eth1 11
- 1
- Name of the Policy.
- 2
- Optional: If you do not include the
nodeSelector
, the Policy applies to all nodes in the cluster. - 3
- This example uses a
hostname
node selector. - 4
- Name of the interface.
- 5
- Optional: Human-readable description of the interface.
- 6
- The type of interface. This example creates a bridge.
- 7
- The requested state for the interface after creation.
- 8
- Optional: If you do not use
dhcp
, you can either set a static IP or leave the interface without an IP address. - 9
- Enables
ipv4
in this example. - 10
- Disables
stp
in this example. - 11
- The node NIC to which the bridge attaches.
11.2.6.2. Example: VLAN interface NodeNetworkConfigurationPolicy
Create a VLAN interface on nodes in the cluster by applying a NodeNetworkConfigurationPolicy
manifest to the cluster.
The following YAML file is an example of a manifest for a VLAN interface. It includes samples values that you must replace with your own information.
apiVersion: nmstate.io/v1alpha1 kind: NodeNetworkConfigurationPolicy metadata: name: vlan-eth1-policy 1 spec: nodeSelector: 2 kubernetes.io/hostname: <node01> 3 desiredState: interfaces: - name: eth1.102 4 description: VLAN using eth1 5 type: vlan 6 state: up 7 vlan: base-iface: eth1 8 id: 102 9
- 1
- Name of the Policy.
- 2
- Optional: If you do not include the
nodeSelector
, the Policy applies to all nodes in the cluster. - 3
- This example uses a
hostname
node selector. - 4
- Name of the interface.
- 5
- Optional: Human-readable description of the interface.
- 6
- The type of interface. This example creates a VLAN.
- 7
- The requested state for the interface after creation.
- 8
- The node NIC to which the VLAN is attached.
- 9
- The VLAN tag.
11.2.6.3. Example: Bond interface NodeNetworkConfigurationPolicy
Create a bond interface on nodes in the cluster by applying a NodeNetworkConfigurationPolicy
manifest to the cluster.
OpenShift Virtualization only supports the following bond modes:
-
mode=1 active-backup
-
mode=5 balance-tlb
- mode=6 balance-alb
The following YAML file is an example of a manifest for a bond interface. It includes samples values that you must replace with your own information.
apiVersion: nmstate.io/v1alpha1 kind: NodeNetworkConfigurationPolicy metadata: name: bond0-eth1-eth2-policy 1 spec: nodeSelector: 2 kubernetes.io/hostname: <node01> 3 desiredState: interfaces: - name: bond0 4 description: Bond enslaving eth1 and eth2 5 type: bond 6 state: up 7 ipv4: dhcp: true 8 enabled: true 9 link-aggregation: mode: active-backup 10 options: miimon: '140' 11 slaves: 12 - eth1 - eth2 mtu: 1450 13
- 1
- Name of the Policy.
- 2
- Optional: If you do not include the
nodeSelector
, the Policy applies to all nodes in the cluster. - 3
- This example uses a
hostname
node selector. - 4
- Name of the interface.
- 5
- Optional: Human-readable description of the interface.
- 6
- The type of interface. This example creates a bond.
- 7
- The requested state for the interface after creation.
- 8
- Optional: If you do not use
dhcp
, you can either set a static IP or leave the interface without an IP address. - 9
- Enables
ipv4
in this example. - 10
- The driver mode for the bond. This example uses an active backup mode.
- 11
- Optional: This example uses miimon to inspect the bond link every 140ms.
- 12
- The subordinate node NICs in the bond.
- 13
- Optional: The maximum transmission unit (MTU) for the bond. If not specified, this value is set to
1500
by default.
11.2.6.4. Example: Ethernet interface NodeNetworkConfigurationPolicy
Configure an Ethernet interface on nodes in the cluster by applying a NodeNetworkConfigurationPolicy
manifest to the cluster.
The following YAML file is an example of a manifest for an Ethernet interface. It includes sample values that you must replace with your own information.
apiVersion: nmstate.io/v1alpha1 kind: NodeNetworkConfigurationPolicy metadata: name: eth1-policy 1 spec: nodeSelector: 2 kubernetes.io/hostname: <node01> 3 desiredState: interfaces: - name: eth1 4 description: Configuring eth1 on node01 5 type: ethernet 6 state: up 7 ipv4: dhcp: true 8 enabled: true 9
- 1
- Name of the Policy.
- 2
- Optional: If you do not include the
nodeSelector
, the Policy applies to all nodes in the cluster. - 3
- This example uses a
hostname
node selector. - 4
- Name of the interface.
- 5
- Optional: Human-readable description of the interface.
- 6
- The type of interface. This example creates an Ethernet networking interface.
- 7
- The requested state for the interface after creation.
- 8
- Optional: If you do not use
dhcp
, you can either set a static IP or leave the interface without an IP address. - 9
- Enables
ipv4
in this example.
11.2.6.5. Example: Multiple interfaces in the same Policy
You can create multiple interfaces in the same Policy. These interfaces can reference each other, allowing you to build and deploy a network configuration by using a single Policy manifest.
The following example snippet creates a bond that is named bond10
across two NICs and a Linux bridge that is named br1
that connects to the bond.
... interfaces: - name: bond10 description: Bonding eth2 and eth3 for Linux bridge type: bond state: up link-aggregation: slaves: - eth2 - eth3 - name: br1 description: Linux bridge on bond type: linux-bridge state: up bridge: port: - name: bond10 ...
11.2.7. Examples: IP management
The following example configuration snippets demonstrate different methods of IP management.
These examples use the ethernet
interface type to simplify the example while showing the related context in the Policy configuration. These IP management examples can be used with the other interface types.
11.2.7.1. Static
The following snippet statically configures an IP address on the Ethernet interface:
...
interfaces:
- name: eth1
description: static IP on eth1
type: ethernet
state: up
ipv4:
address:
- ip: 192.168.122.250 1
prefix-length: 24
enabled: true
...
- 1
- Replace this value with the static IP address for the interface.
11.2.7.2. No IP address
The following snippet ensures that the interface has no IP address:
... interfaces: - name: eth1 description: No IP on eth1 type: ethernet state: up ipv4: enabled: false ...
11.2.7.3. Dynamic host configuration
The following snippet configures an Ethernet interface that uses a dynamic IP address, gateway address, and DNS:
... interfaces: - name: eth1 description: DHCP on eth1 type: ethernet state: up ipv4: dhcp: true enabled: true ...
The following snippet configures an Ethernet interface that uses a dynamic IP address but does not use a dynamic gateway address or DNS:
... interfaces: - name: eth1 description: DHCP without gateway or DNS on eth1 type: ethernet state: up ipv4: dhcp: true auto-gateway: false auto-dns: false enabled: true ...
11.2.7.4. DNS
The following snippet sets DNS configuration on the host.
... interfaces: ... dns-resolver: config: search: - example.com - example.org server: - 8.8.8.8 ...
11.2.7.5. Static routing
The following snippet configures a static route and a static IP on interface eth1
.
... interfaces: - name: eth1 description: Static routing on eth1 type: ethernet state: up ipv4: address: - ip: 192.0.2.251 1 prefix-length: 24 enabled: true routes: config: - destination: 198.51.100.0/24 metric: 150 next-hop-address: 192.0.2.1 2 next-hop-interface: eth1 table-id: 254 ...