How to try out nested-pods locally (VLAN + trunk)

Following are the instructions for an all-in-one setup where K8s will also be running inside the same Nova VM in which Kuryr-controller and Kuryr-cni will be running. 4GB memory and 2 vCPUs, is the minimum resource requirement for the VM:

1. To install OpenStack services run devstack with devstack/local.conf.pod-in-vm.undercloud.sample. Ensure that “trunk” service plugin is enabled in /etc/neutron/neutron.conf:

   [DEFAULT]
   service_plugins = neutron.services.l3_router.l3_router_plugin.L3RouterPlugin,neutron.services.trunk.plugin.TrunkPlugin
   

2. Launch a VM with Neutron trunk port.

3. Inside VM, install and setup Kubernetes along with Kuryr using devstack:

   • Since undercloud Neutron will be used by pods, Neutron services should be disabled in localrc.
   • Run devstack with devstack/local.conf.pod-in-vm.overcloud.sample. With this config devstack will not configure Neutron resources for the local cloud. These variables have to be added manually to /etc/kuryr/kuryr.conf.

4. Once devstack is done and all services are up inside VM:

   • Configure /etc/kuryr/kuryr.conf to set UUID of Neutron resources from undercloud Neutron:

     [neutron_defaults]
     ovs_bridge = br-int
     pod_security_groups = <UNDERCLOUD_DEFAULT_SG_UUID>
     pod_subnet = <UNDERCLOUD_SUBNET_FOR_PODS_UUID>
     project = <UNDERCLOUD_DEFAULT_PROJECT_UUID>
     service_subnet = <UNDERCLOUD_SUBNET_FOR_SERVICES_UUID>
     

   • Configure worker VMs subnet:

     [pod_vif_nested]
     worker_nodes_subnet = <UNDERCLOUD_SUBNET_WORKER_NODES_UUID>
     

   • Configure “pod_vif_driver” as “nested-vlan”:

     [kubernetes]
     pod_vif_driver = nested-vlan
     

   • Configure binding section:

     [binding]
     driver = kuryr.lib.binding.drivers.vlan
     link_iface = <VM interface name eg. eth0>
     

   • Restart kuryr-k8s-controller:

     sudo systemctl restart devstack@kuryr-kubernetes.service
     

Now launch pods using kubectl, Undercloud Neutron will serve the networking.