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OKD - Create a Homelab Cluster - finalizing the setup process

We'll be working on the Servers that are surrounded by the continous lines in this drawing:

The Cluster is in the process of building if you've arrived here. However, there's still some steps left to do like:

  • remove the bootstrap node from haproxy
  • approve the signing requests for the worker nodes
  • monitor the cluster state and cluster operators
  • create an initial htpasswd auth provider for a fallback admin account
  • create a storage class for the openshift internal image registry
Let's start with removing the bootstrap Node after the bootstrap monitoring command tells us it's safe to remove:
 [archy@helper01 ~]# sudo vim /etc/haproxy/haproxy.cfg  
 [archy@helper02 ~]# sudo vim /etc/haproxy/haproxy.cfg  
 global  
   log 127.0.0.1 local2  
   pidfile /var/run/haproxy.pid  
   maxconn 4000  
   daemon  
 defaults  
   mode http  
   log global  
   option dontlognull  
   option http-server-close  
   option redispatch  
   retries 3  
   timeout http-request 10s  
   timeout queue 1m  
   timeout connect 10s  
   timeout client 1m  
   timeout server 1m  
   timeout http-keep-alive 10s  
   timeout check 10s  
   maxconn 3000  
 frontend stats  
   bind 0.0.0.0:9000  
   mode http  
   log global  
   maxconn 10  
   stats enable  
   stats hide-version  
   stats refresh 30s  
   stats show-node  
   stats show-desc Stats for ha service  
   stats uri /stats  
 listen api-server-6443  
   bind 0.0.0.0:6443  
   mode tcp    
   server master01 master01.okd.archyslife.lan:6443 check inter 1s  
   server master02 master02.okd.archyslife.lan:6443 check inter 1s  
   server master03 master03.okd.archyslife.lan:6443 check inter 1s  
 listen machine-config-server-22623  
   bind 0.0.0.0:22623  
   mode tcp    
   server master01 master01.okd.archyslife.lan:22623 check inter 1s  
   server master02 master02.okd.archyslife.lan:22623 check inter 1s  
   server master03 master03.okd.archyslife.lan:22623 check inter 1s  
 listen http-ingress-80  
   bind 0.0.0.0:80  
   mode tcp  
   server worker01 worker01.okd.archyslife.lan:80 check inter 1s  
   server worker02 worker02.okd.archyslife.lan:80 check inter 1s  
 listen https-ingress-443  
   bind 0.0.0.0:443  
   mode tcp  
   server worker01 worker01.okd.archyslife.lan:443 check inter 1s  
   server worker02 worker02.okd.archyslife.lan:443 check inter 1s  

With the bootstrap node removed, you can shut it down but I'd recommend to not delete it yet.
Next step is approving the CSRs generated by the worker nodes:
 [root@helper01 ~]# export KUBECONFIG=/root/openshift-installer/auth/kubeconfig  
 [root@helper01 ~]# oc get nodes -o wide --show-kind  
 [root@helper01 ~]# oc get csr -ojson | jq -r '.items[] | select(.status == {} ) | .metadata.name' | xargs oc adm certificate approve  
These commands might need to be repeated multiple times until all nodes are joined.
Once all nodes are part of the cluster, you can continue with monitoring the setup process by using these commands:
 [root@helper01 ~]# watch -cn 1 oc get clusteroperators -o wide --show-kind  
 [root@helper01 ~]# watch -cn 1 oc get pods -o wide --show-kind --all-namespaces  
After all the cluster operators are in a running state and are not progressing anymore, we can start to customize the installation. I'll start by adding a htpasswd authentication source as a fallback admin (adding other authentication sources will not be part of this tutorial) and add a default storage class using the nfs-subdir-provisioner. Setting up a htpasswd auth provider is fairly simple:
 [root@helper01 ~]# htpasswd -c -B ~/openshift-installer/htpasswd-initial admin  
 [root@helper01 ~]# oc -n openshift-config create secret generic htpasswd-initial --from-file htpasswd=${HOME}/openshift-installer/htpasswd-initial  
 [root@helper01 ~]# cat << EOF >> ~/openshift-installer/htpasswd-initial.yaml  
 ---  
 apiVersion: config.openshift.io/v1  
 kind: OAuth  
 metadata:  
  name: cluster  
 spec:  
  identityProviders:  
    - name: htpasswd-initial  
      mappingMethod: claim  
      type: HTPasswd  
      htpasswd:  
        fileData:  
          name: htpasswd-initial  
 ...  
 EOF  
 [root@helper01 ~]# oc apply -f ${HOME}/openshift-installer/htpasswd-initial.yaml  
Monitor the rollout process using this command:
 [root@helper01 ~]# watch -cn 1 oc -n openshift-authentication get pods -o wide --show-kind  
Once all the pods are restarted, associate the the 'cluster-admin' cluster-role to the 'admin' user:
 [root@helper01 ~]# CLUSTERNAME=okd  
 [root@helper01 ~]# BASEDOMAIN=archyslife.lan  
 [root@helper01 ~]# oc login -u 'admin' -p '' --insecure-skip-tls-verify "https://api.${CLUSTERNAME}.${BASEDOMAIN}:6443"  
The last step in finalizing the initial setup, is creating a storage class. I'll be using a nas in my local network along with the nfs-subdir-provisioner. First, some preparations:
 [root@helper01 ~]# git clone https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner.git  
 [root@helper01 ~]# cd nfs-subdir-external-provisioner  
 [root@helper01 ~]# NAMESPACE=default  
 [root@helper01 ~]# sed -i'' "s/namespace:.*/namespace: ${NAMESPACE}/g" ./deploy/rbac.yaml ./deploy/deployment.yaml  
 [root@helper01 ~]# oc create -f deploy/rbac.yaml  
 [root@helper01 ~]# oc adm policy add-scc-to-user hostmount-anyuid system:serviceaccount:${NAMESPACE}:nfs-client-provisioner  
Next, edit and apply the deployment, here's mine as a reference:
 [root@helper01 ~]# cat deploy/deployment.yaml  
 apiVersion: apps/v1  
 kind: Deployment  
 metadata:  
   namespace: default
   name: nfs-client-provisioner  
   labels:  
     app: nfs-client-provisioner      
 spec:  
   replicas: 1  
   revisionHistoryLimit: 5  
   strategy:  
     type: Recreate  
   selector:  
     matchLabels:  
       app: nfs-client-provisioner  
   template:  
     metadata:  
      labels:  
        app: nfs-client-provisioner  
     spec:  
       serviceAccountName: nfs-client-provisioner  
       containers:  
         - name: nfs-client-provisioner  
           image: registry.k8s.io/sig-storage/nfs-subdir-external-provisioner:v4.0.2  
           volumeMounts:  
             - name: nfs-client-root  
               mountPath: /persistentvolumes  
           env:  
             - name: PROVISIONER_NAME  
               value: k8s-sigs.io/nfs-subdir-external-provisioner  
             - name: NFS_SERVER  
               value: strgnas01.archyslife.lan  
             - name: NFS_PATH  
               value: /volume1/openshift-data  
       volumes:  
         - name: nfs-client-root  
           nfs:  
             server: strgnas01.archyslife.lan  
             path: /volume1/openshift-data  
 [root@helper01 ~]# oc -n default apply -f deploy/deployment.yaml  
 [root@helper01 ~]# oc -n default get pods -o wide  
Once the pod is running, create the storage class:
 [root@helper01 ~]# cat << EOF >> deploy/class.yaml  
 ---  
 apiVersion: storage.k8s.io/v1  
 kind: StorageClass  
 metadata:  
   name: managed-nfs  
   annotations:  
     storageclass.kubernetes.io/is-default-class: "true"  
 provisioner: k8s-sigs.io/nfs-subdir-external-provisioner  
 parameters:  
   pathPattern: "${.PVC.namespace}-${.PVC.name}"  
   archiveOnDelete: "false"  
 ...  
 EOF  
 [root@helper01 ~]# oc apply -f deploy/class.yaml  
That's all there is to deploying the storage class in OKD / OpenShift. PVCs will now use this storage class by default due to its annotation. 

Feel free to comment and / or suggest a topic.


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