OpenShift docs are moving and will soon only be available at docs.redhat.com, the home of all Red Hat product documentation. Explore the new docs experience today.
  1. Documentation
    2. history bug_report picture_as_pdf
×

Configuring an SR-IOV InfiniBand network attachment

InfiniBand device configuration object

You can configure an InfiniBand (IB) network device by defining an SriovIBNetwork object.

The following YAML describes an SriovIBNetwork object:

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovIBNetwork
metadata:
  name: <name> (1)
  namespace: openshift-sriov-network-operator (2)
spec:
  resourceName: <sriov_resource_name> (3)
  networkNamespace: <target_namespace> (4)
  ipam: |- (5)
    {}
  linkState: <link_state> (6)
  capabilities: <capabilities> (7)
1 A name for the object. The SR-IOV Network Operator creates a NetworkAttachmentDefinition object with same name.
2 The namespace where the SR-IOV Operator is installed.
3 The value for the spec.resourceName parameter from the SriovNetworkNodePolicy object that defines the SR-IOV hardware for this additional network.
4 The target namespace for the SriovIBNetwork object. Only pods in the target namespace can attach to the network device.
5 Optional: A configuration object for the IPAM CNI plugin as a YAML block scalar. The plugin manages IP address assignment for the attachment definition.
6 Optional: The link state of virtual function (VF). Allowed values are enable, disable and auto.
7 Optional: The capabilities to configure for this network. You can specify '{ "ips": true }' to enable IP address support or '{ "infinibandGUID": true }' to enable IB Global Unique Identifier (GUID) support.

Configuration of IP address assignment for an additional network

The IP address management (IPAM) Container Network Interface (CNI) plugin provides IP addresses for other CNI plugins.

You can use the following IP address assignment types:

  • Static assignment.

  • Dynamic assignment through a DHCP server. The DHCP server you specify must be reachable from the additional network.

  • Dynamic assignment through the Whereabouts IPAM CNI plugin.

Static IP address assignment configuration

The following table describes the configuration for static IP address assignment:

Table 1. ipam static configuration object
Field Type Description

type

string

The IPAM address type. The value static is required.

addresses

array

An array of objects specifying IP addresses to assign to the virtual interface. Both IPv4 and IPv6 IP addresses are supported.

routes

array

An array of objects specifying routes to configure inside the pod.

dns

array

Optional: An array of objects specifying the DNS configuration.

The addresses array requires objects with the following fields:

Table 2. ipam.addresses[] array
Field Type Description

address

string

An IP address and network prefix that you specify. For example, if you specify 10.10.21.10/24, then the additional network is assigned an IP address of 10.10.21.10 and the netmask is 255.255.255.0.

gateway

string

The default gateway to route egress network traffic to.
Table 3. ipam.routes[] array
Field Type Description

dst

string

The IP address range in CIDR format, such as 192.168.17.0/24 or 0.0.0.0/0 for the default route.

gw

string

The gateway where network traffic is routed.
Table 4. ipam.dns object
Field Type Description

nameservers

array

An array of one or more IP addresses for to send DNS queries to.

domain

array

The default domain to append to a hostname. For example, if the domain is set to example.com, a DNS lookup query for example-host is rewritten as example-host.example.com.

search

array

An array of domain names to append to an unqualified hostname, such as example-host, during a DNS lookup query.
Static IP address assignment configuration example
{
  "ipam": {
    "type": "static",
      "addresses": [
        {
          "address": "191.168.1.7/24"
        }
      ]
  }
}

Dynamic IP address (DHCP) assignment configuration

The following JSON describes the configuration for dynamic IP address address assignment with DHCP.

Renewal of DHCP leases

A pod obtains its original DHCP lease when it is created. The lease must be periodically renewed by a minimal DHCP server deployment running on the cluster.

To trigger the deployment of the DHCP server, you must create a shim network attachment by editing the Cluster Network Operator configuration, as in the following example:

Example shim network attachment definition
apiVersion: operator.openshift.io/v1
kind: Network
metadata:
  name: cluster
spec:
  additionalNetworks:
  - name: dhcp-shim
    namespace: default
    type: Raw
    rawCNIConfig: |-
      {
        "name": "dhcp-shim",
        "cniVersion": "0.3.1",
        "type": "bridge",
        "ipam": {
          "type": "dhcp"
        }
      }
  # ...
Table 5. ipam DHCP configuration object
Field Type Description

type

string

The IPAM address type. The value dhcp is required.
Dynamic IP address (DHCP) assignment configuration example
{
  "ipam": {
    "type": "dhcp"
  }
}

Dynamic IP address assignment configuration with Whereabouts

The Whereabouts CNI plugin allows the dynamic assignment of an IP address to an additional network without the use of a DHCP server.

The Whereabouts CNI plugin also supports overlapping IP address ranges and configuration of the same CIDR range multiple times within separate NetworkAttachmentDefinitions. This provides greater flexibility and management capabilities in multi-tenant environments.

Dynamic IP address configuration objects

The following table describes the configuration objects for dynamic IP address assignment with Whereabouts:

Table 6. ipam whereabouts configuration object
Field Type Description

type

string

The IPAM address type. The value whereabouts is required.

range

string

An IP address and range in CIDR notation. IP addresses are assigned from within this range of addresses.

exclude

array

Optional: A list of zero or more IP addresses and ranges in CIDR notation. IP addresses within an excluded address range are not assigned.

network_name

string

Optional: Helps ensure that each group or domain of pods gets its own set of IP addresses, even if they share the same range of IP addresses. Setting this field is important for keeping networks separate and organized, notably in multi-tenant environments.
Dynamic IP address assignment configuration that uses Whereabouts

The following example shows a dynamic address assignment configuration that uses Whereabouts:

Whereabouts dynamic IP address assignment
{
  "ipam": {
    "type": "whereabouts",
    "range": "192.0.2.192/27",
    "exclude": [
       "192.0.2.192/30",
       "192.0.2.196/32"
    ]
  }
}
Dynamic IP address assignment that uses Whereabouts with overlapping IP address ranges

The following example shows a dynamic IP address assignment that uses overlapping IP address ranges for multi-tenant networks.

NetworkAttachmentDefinition 1
{
  "ipam": {
    "type": "whereabouts",
    "range": "192.0.2.192/29",
    "network_name": "example_net_common", (1)
  }
}
1 Optional. If set, must match the network_name of NetworkAttachmentDefinition 2.
NetworkAttachmentDefinition 2
{
  "ipam": {
    "type": "whereabouts",
    "range": "192.0.2.192/24",
    "network_name": "example_net_common", (1)
  }
}
1 Optional. If set, must match the network_name of NetworkAttachmentDefinition 1.

Creating a configuration for assignment of dual-stack IP addresses dynamically

Dual-stack IP address assignment can be configured with the ipRanges parameter for:

  • IPv4 addresses

  • IPv6 addresses

  • multiple IP address assignment

Procedure

  1. Set type to whereabouts.

  2. Use ipRanges to allocate IP addresses as shown in the following example:

    cniVersion: operator.openshift.io/v1
kind: Network
=metadata:
  name: cluster
spec:
  additionalNetworks:
  - name: whereabouts-shim
    namespace: default
    type: Raw
    rawCNIConfig: |-
      {
       "name": "whereabouts-dual-stack",
       "cniVersion": "0.3.1,
       "type": "bridge",
       "ipam": {
         "type": "whereabouts",
         "ipRanges": [
                  {"range": "192.168.10.0/24"},
                  {"range": "2001:db8::/64"}
              ]
       }
      }

  3. Attach network to a pod. For more information, see "Adding a pod to an additional network".

  4. Verify that all IP addresses are assigned.

  5. Run the following command to ensure the IP addresses are assigned as metadata.

    $ oc exec -it mypod -- ip a
Additional resources

Configuring SR-IOV additional network

You can configure an additional network that uses SR-IOV hardware by creating an SriovIBNetwork object. When you create an SriovIBNetwork object, the SR-IOV Network Operator automatically creates a NetworkAttachmentDefinition object.

Do not modify or delete an SriovIBNetwork object if it is attached to any pods in a running state.
Prerequisites

  • Install the OpenShift CLI (oc).

  • Log in as a user with cluster-admin privileges.

Procedure

  1. Create a SriovIBNetwork object, and then save the YAML in the <name>.yaml file, where <name> is a name for this additional network. The object specification might resemble the following example:

    apiVersion: sriovnetwork.openshift.io/v1
kind: SriovIBNetwork
metadata:
  name: attach1
  namespace: openshift-sriov-network-operator
spec:
  resourceName: net1
  networkNamespace: project2
  ipam: |-
    {
      "type": "host-local",
      "subnet": "10.56.217.0/24",
      "rangeStart": "10.56.217.171",
      "rangeEnd": "10.56.217.181",
      "gateway": "10.56.217.1"
    }

  2. To create the object, enter the following command:

    $ oc create -f <name>.yaml

    where <name> specifies the name of the additional network.

  3. Optional: To confirm that the NetworkAttachmentDefinition object that is associated with the SriovIBNetwork object that you created in the previous step exists, enter the following command. Replace <namespace> with the networkNamespace you specified in the SriovIBNetwork object.

    $ oc get net-attach-def -n <namespace>

Next steps

Additional resources