L2 template example with bonds and bridges

This section contains an exemplary L2 template that demonstrates how to set up bonds and bridges on hosts for your managed clusters as described in Create L2 templates.

Caution

Use of a dedicated network for Kubernetes pods traffic, for external connection to the Kubernetes services exposed by the cluster, and for the Ceph cluster access and replication traffic is available as Technology Preview. Use such configurations for testing and evaluation purposes only. For the Technology Preview feature definition, refer to Technology Preview support scope.

The following feature is still under development and will be announced in one of the following Container Cloud releases:

  • Switching Kubernetes API to listen to the specified IP address on the node

Dedicated network for the Kubernetes pods traffic

If you want to use a dedicated network for Kubernetes pods traffic, configure each node with an IPv4 and/or IPv6 address that will be used to route the pods traffic between nodes. To accomplish that, use the npTemplate.bridges.k8s-pods bridge in the L2 template, as demonstrated in the example below. As defined in Host networking, this bridge name is reserved for the Kubernetes pods network. When the k8s-pods bridge is defined in an L2 template, Calico CNI uses that network for routing the pods traffic between nodes.

Dedicated network for the Kubernetes services traffic (MetalLB)

You can use a dedicated network for external connection to the Kubernetes services exposed by the cluster. If enabled, MetalLB will listen and respond on the dedicated virtual bridge. To accomplish that, configure each node where metallb-speaker is deployed with an IPv4 or IPv6 address. Both the MetalLB IP address ranges and the IP addresses configured on those nodes must fit in the same CIDR.

Use the npTemplate.bridges.k8s-ext bridge in the L2 template, as demonstrated in the example below. This bridge name is reserved for the Kubernetes external network. The Subnet object that corresponds to the k8s-ext bridge must have explicitly excluded the IP address ranges that are in use by MetalLB.

Dedicated network for the Ceph distributed storage traffic

You can configure dedicated networks for the Ceph cluster access and replication traffic. Set labels on the Subnet CRs for the corresponding networks, as described in Create subnets. Container Cloud automatically configures Ceph to use the addresses from these subnets. Ensure that the addresses are assigned to the storage nodes.

Use the npTemplate.bridges.ceph-cluster and npTemplate.bridges.ceph-replication bridges in the L2 template, as demonstrated in the example below. These names are reserved for the Ceph cluster access and replication networks.

The Subnet objects used to assign IP addresses to these bridges must have corresponding labels ipam/SVC-ceph-public for the ceph-cluster bridge and ipam/SVC-ceph-cluster for the ceph-replication bridge.

Example of an L2 template with interfaces bonding

apiVersion: ipam.mirantis.com/v1alpha1
kind: L2Template
metadata:
  name: test-managed
  namespace: managed-ns
spec:
  clusterRef: managed-cluster
  autoIfMappingPrio:
    - provision
    - eno
    - ens
    - enp
  l3Layout:
    - subnetName: pxe-subnet
      scope:      global
    - subnetName: demo-pods
      scope:      namespace
    - subnetName: demo-ext
      scope:      namespace
    - subnetName: demo-ceph-cluster
      scope:      namespace
    - subnetName: demo-ceph-replication
      scope:      namespace
  npTemplate: |
    version: 2
    ethernets:
      ten10gbe0s0:
        dhcp4: false
        dhcp6: false
        match:
          macaddress: {{mac 2}}
        set-name: {{nic 2}}
      ten10gbe0s1:
        dhcp4: false
        dhcp6: false
        match:
          macaddress: {{mac 3}}
        set-name: {{nic 3}}
    bonds:
      bond0:
        interfaces:
          - ten10gbe0s0
          - ten10gbe0s1
    vlans:
      k8s-ext-vlan:
        id: 1001
        link: bond0
      k8s-pods-vlan:
        id: 1002
        link: bond0
      ceph-cluster-vlan:
        id: 1003
        link: bond0
      ceph-replication-vlan:
        id: 1004
        link: bond0
    bridges:
      k8s-ext:
        interfaces: [k8s-ext-vlan]
        addresses:
          - {{ip "k8s-ext:demo-ext"}}
      k8s-pods:
        interfaces: [k8s-pods-vlan]
        addresses:
          - {{ip "k8s-pods:demo-pods"}}
      ceph-cluster:
        interfaces: [ceph-cluster-vlan]
        addresses:
          - {{ip "ceph-cluster:demo-ceph-cluster"}}
      ceph-replication:
        interfaces: [ceph-replication-vlan]
        addresses:
          - {{ip "ceph-replication:demo-ceph-replication"}}