.. multi-node: ================================= Kolla Kubernetes Multi-Node Guide ================================= This guide documents how to deploy Kolla-Kubernetes within a multi-node Kubernetes cluster. It will guide you through all of the dependencies required to deploy Horizon, the OpenStack Admin Web Interface. It works for Kubernetes clusters supporting various storage providers including GCE compute disks, AWS EBS, Ceph RBD, and even local host mounts if you are developing multi-node on an all-in-one system. This is an advanced guide. Before attempting to deploy on a multi-node cluster, please follow the :doc:`quickstart` and ensure that you have successfully deployed Kolla-Kubernetes on a single host using the :doc:`kubernetes-all-in-one`. This multi-node guide requires quite a few system dependencies to be addressed by the :doc:`quickstart`. Following this guide will result in a minimal Kolla-Kubernetes multi-node deployment consisting of: - 1 mariadb instance - 1 memcached instance - 3 keystone instances - 3 horizon instances The end result will be a working Horizon admin interface and its dependencies deployed with all of the self-healing and auto-wiring benefits that a Kubernetes cluster has to offer. You should be able to destroy Kubernetes nodes at will, and the system should self-heal and maintain state as pods migrate from destroyed nodes to new nodes. You may also destroy *all* Kubernetes nodes, then bring some back, and the system should again self-heal. Because we are using network volumes, mariadb state is maintained since its network volume will follow the pod as it is rescheduled from one node to the next. Pre-Requisites ============== Follow the :doc:`quickstart`, configure your system, and do a "Development Install" of Kolla and Kolla-Kubernetes. This is absolutely required. Configure Kolla =============== For multi-node deployments, a Docker registry is required since the Kubernetes nodes will not be able to find the Kolla images that your development machine has built. Thus, we must configure Kolla to name the images correctly, so that we may easily push the images to the right Docker registry. Add your Docker registry settings in the Kolla-Ansible configuration file ```./etc/kolla/globals.yml```. :: # Edit Kolla-Ansible config ./etc/kolla/globals.yml docker_registry: "" # e.g. "gcr.io" docker_namespace: "" # e.g. "annular-reef-123" Generate the Kolla configurations, build the Kolla images, and push the Kolla images to your Docker registry. :: # Generate the Kolla-Ansible configurations pushd kolla-ansible sudo ./tools/generate_passwords.py # (Optional: will overwrite) sudo ./tools/kolla-ansible genconfig popd Build Kolla Images and Push to Docker Registry ============================================== :: # Set env variables to make subsequent commands cut-and-pasteable export DOCKER_REGISTRY="" export DOCKER_NAMESPACE="" export DOCKER_TAG="4.0.0" export KOLLA_CONTAINERS="mariadb memcached kolla-toolbox keystone horizon" # Build the Kolla containers kolla-build $KOLLA_CONTAINERS --registry $DOCKER_REGISTRY --namespace $DOCKER_NAMESPACE # Authenticate with your Docker registry # This may not be necessary if you are using a cloud provider docker login # Push the newly-built Kolla containers to your Docker registry # For GKE, change the command below to be "gcloud docker push" for i in $KOLLA_CONTAINERS; do docker push "$DOCKER_REGISTRY/$DOCKER_NAMESPACE/centos-binary-$i:$DOCKER_TAG" done Configure Kolla-Kubernetes ========================== Modify the Kolla-Kubernetes configuration file ```./etc/kolla-kubernetes/kolla-kubernetes.yml``` to set the number of instance replicas. In addition, set the storage_provider settings to match your environment. :: # Edit Kolla-Kubernetes config ./etc/kolla-kubernetes/kolla-kubernetes.yml ######################## # Kubernetes Cluster ######################## keystone_replicas: "3" horizon_replicas: "3" ######################## # Persistent Storage ######################## storage_provider: "host" # host, ceph, gce, aws storage_ceph: keyring: /etc/ceph/ceph.client.admin.keyring monitors: - x.x.x.x - y.y.y.y pool: rbd secretName: pkt-ceph-secret ssh_user: root user: admin Known Issues ============ #1. On GCE, the mariadb pod is unable to mount the network drive that was prior mounted by the mariadb-bootstrap job, until the mariadb-bootstrap job is deleted. The same should also occur for AWS and Ceph. #2. When running Kubernetes, Ceph RBD volumes will not auto-unlock when Kubernetes nodes disappear, causing problems when a pod migrates to a new node and cannot mount the required volume. This was supposed to have been fixed in Kubernetes 1.3, but we have been unable to verify it working. Details are found in the in this `kubernetes pull request `_. Create all Kolla-Kubernetes Resources ===================================== Execute the following commands to create the Kolla-Kubernetes multi-node cluster. There are two unique perspectives, that of an operator and that of a workflow engine. The workflow engine drives the same CLI subcommands that are accessible to operators. However, since the workflow engine does not yet exist, the shortcut workflow commands as defined in the quickstart are still supported. All of the commands below are cut and pasteable. Operator Create Resources ------------------------- :: kolla-kubernetes bootstrap ceph # adds ceph secret, no-op for storage_provider!=ceph kolla-kubernetes bootstrap mariadb sleep 30 # wait for mariadb bootstrap to finish kolla-kubernetes resource delete bootstrap mariadb # workaround known issue #1 kolla-kubernetes run mariadb kolla-kubernetes run memcached sleep 30 # wait for mariadb and memcached to start up kolla-kubernetes bootstrap keystone sleep 30 # wait for keystone to bootstrap in mariadb kolla-kubernetes run keystone sleep 30 # wait for keystone to start up kolla-kubernetes run horizon Workflow Engine Create Resources -------------------------------- A future Ansible Workflow Engine would individually call the discrete bits of logic. :: kolla-kubernetes resource create disk mariadb kolla-kubernetes resource create pv mariadb kolla-kubernetes resource create pvc mariadb kolla-kubernetes resource create svc mariadb kolla-kubernetes resource create configmap mariadb kolla-kubernetes resource create bootstrap mariadb sleep 30 # wait for mariadb bootstrap to finish kolla-kubernetes resource delete bootstap mariadb # workaround known issue #1 kolla-kubernetes resource create pod mariadb kolla-kubernetes resource create svc memcached kolla-kubernetes resource create configmap memcached kolla-kubernetes resource create pod memcached kolla-kubernetes resource create svc keystone kolla-kubernetes resource create configmap keystone sleep 30 # wait for mariadb and memcached to start up kolla-kubernetes resource create bootstrap keystone sleep 30 # wait for keystone to bootstrap in mariadb kolla-kubernetes resource create pod keystone kolla-kubernetes resource create svc horizon kolla-kubernetes resource create configmap horizon sleep 30 # wait for keystone to start up kolla-kubernetes resource create pod horizon Check Status of all Kolla-Kubernetes Resources ============================================== Checking status is the same whether for operators or workflow engine. :: kolla-kubernetes resource status disk mariadb kolla-kubernetes resource status pv mariadb kolla-kubernetes resource status pvc mariadb kolla-kubernetes resource status svc mariadb kolla-kubernetes resource status configmap mariadb kolla-kubernetes resource status bootstrap mariadb kolla-kubernetes resource status pod mariadb kolla-kubernetes resource status svc memcached kolla-kubernetes resource status configmap memcached kolla-kubernetes resource status pod memcached kolla-kubernetes resource status svc keystone kolla-kubernetes resource status configmap keystone kolla-kubernetes resource status bootstrap keystone kolla-kubernetes resource status pod keystone kolla-kubernetes resource status svc horizon kolla-kubernetes resource status configmap horizon kolla-kubernetes resource status pod horizon Delete all Kolla-Kubernetes Resources ===================================== Deleting all resources is exactly executing the creation steps in reverse. Operator Delete Resources ------------------------- :: kolla-kubernetes kill horizon kolla-kubernetes kill keystone kolla-kubernetes kill memcached kolla-kubernetes kill mariadb kolla-kubernetes kill ceph Workflow Engine Delete Resources -------------------------------- :: kolla-kubernetes resource delete pod horizon kolla-kubernetes resource delete configmap horizon kolla-kubernetes resource delete svc horizon kolla-kubernetes resource delete pod keystone kolla-kubernetes resource delete bootstrap keystone kolla-kubernetes resource delete configmap keystone kolla-kubernetes resource delete svc keystone kolla-kubernetes resource delete pod memcached kolla-kubernetes resource delete configmap memcached kolla-kubernetes resource delete svc memcached kolla-kubernetes resource delete pod mariadb kolla-kubernetes resource delete bootstrap mariadb kolla-kubernetes resource delete configmap mariadb kolla-kubernetes resource delete svc mariadb kolla-kubernetes resource delete pvc mariadb kolla-kubernetes resource delete pv mariadb kolla-kubernetes resource delete disk mariadb