From Zero to Openshift in 30 Minutes

Discover how to leverage the power of kcli and libvirt to rapidly deploy a full OpenShift cluster in under 30 minutes, cutting through the complexity often associated with OpenShift installations.  

Prerequisites

Server with 8+ cores, minimum of 64GB RAM (96+ for >1 worker node)
Fast IO
– dedicated NVMe libvirt storage or
– NVMe LVMCache fronting HDD (surprisingly effective!)
OS installed (tested with CentOS Stream 8)
Packages libvirt + git installed
Pull-secret (store in openshift_pull.json) obtained from https://cloud.redhat.com/openshift/install/pull-secret

Install kcli

[steve@shift ~]$ git clone https://github.com/karmab/kcli.git
[steve@shift ~]$ cd kcli; ./install.sh

Configure parameters.yml


(see https://kcli.readthedocs.io/en/latest/#deploying-kubernetes-openshift-clusters)

example:-

[steve@shift ~]$ cat parameters.yml
cluster: shift413
domain: shift.local
version: stable
tag: '4.13'
ctlplanes: 3
workers:3
ctlplane_memory:16384
worker_memory:16384
ctlplane_numcpus: 8
worker_numcpus: 4

Note 1: To deploy Single Node Openshift (SNO) set ctlplanes to 1 and workers to 0.

Note 2: Even a fast Xeon with NVMe storage may have difficulty deploying more than 3 workers before the installer times out.
An RFE exists to make the timeout configurable, see:

https://access.redhat.com/solutions/6379571
https://issues.redhat.com/browse/RFE-2512

Deploy cluster

[steve@shift ~]$ kcli create kube openshift --paramfile parameters.yml $cluster

Note: openshift_pull.json and parameters.yml should be in your current working directory, or adjust above as required

Monitor Progress

If you wish to monitor progress, find IP of bootsrap node:-

[steve@shift ~]$ virsh net-dhcp-leases default
 Expiry Time           MAC address         Protocol   IP address           Hostname            Client ID or DUID
---------------------------------------------------------------------------------------------------------------------
 2023-07-19 15:48:02   52:54:00:08:41:71   ipv4       192.168.122.103/24   ocp413-ctlplane-0   01:52:54:00:08:41:71
 2023-07-19 15:48:02   52:54:00:10:2a:9d   ipv4       192.168.122.100/24   ocp413-ctlplane-1   01:52:54:00:10:2a:9d
 2023-07-19 15:46:30   52:54:00:2b:98:2a   ipv4       192.168.122.211/24   ocp413-bootstrap    01:52:54:00:2b:98:2a
 2023-07-19 15:48:03   52:54:00:aa:d7:02   ipv4       192.168.122.48/24    ocp413-ctlplane-2   01:52:54:00:aa:d7:02

then ssh to bootstrap node as core user and follow instructions:-

[steve@shift ~]# ssh core@192.168.122.231
journalctl -b -f -u release-image.service -u bootkube.service
Once cluster is deployed you'll receive the following message:-

INFO Waiting up to 40m0s (until 3:42PM) for the cluster at https://api.ocp413.lab.local:6443 to initialize...
INFO Checking to see if there is a route at openshift-console/console...
INFO Install complete!                            
INFO To access the cluster as the system:admin user when using 'oc', run 'export KUBECONFIG=/root/.kcli/clusters/ocp413/auth/kubeconfig'
INFO Access the OpenShift web-console here: https://console-openshift-console.apps.ocp413.lab.local
INFO Login to the console with user: "kubeadmin", and password: "qTT5W-F5Cjz-BIPx2-KWXQx"
INFO Time elapsed: 16m18s                        
Deleting ocp413-bootstrap

Note: Whilst the above credentials can be found later, it’s worthwhile making a note of the above.  I save to a text file on the host.

Confirm Status

[root@shift ~]# export KUBECONFIG=/root/.kcli/clusters/ocp413/auth/kubeconfig
[root@lab ~]# oc status
In project default on server https://api.ocp413.lab.local:6443
svc/openshift - kubernetes.default.svc.cluster.local
svc/kubernetes - 172.30.0.1:443 -> 6443
View details with 'oc describe <resource>/<name>' or list resources with 'oc get all'.
[root@shift ~]# oc get nodes
NAME                          STATUS   ROLES                  AGE   VERSION
ocp413-ctlplane-0.lab.local   Ready    control-plane,master   68m   v1.26.5+7d22122
ocp413-ctlplane-1.lab.local   Ready    control-plane,master   68m   v1.26.5+7d22122
ocp413-ctlplane-2.lab.local   Ready    control-plane,master   68m   v1.26.5+7d22122
ocp413-worker-0.lab.local     Ready    worker                 51m   v1.26.5+7d22122
ocp413-worker-1.lab.local     Ready    worker                 51m   v1.26.5+7d22122
ocp413-worker-2.lab.local     Ready    worker                 52m   v1.26.5+7d22122
[root@shift ~]# oc get clusterversion
NAME      VERSION   AVAILABLE   PROGRESSING   SINCE   STATUS
version   4.13.4    True        False         42m     Cluster version is 4.13.4

And logging in via https://console-openshift-console.apps.ocp413.lab.local/ 

Note: If the cluster is not installed on your workstation, it’s may be easier to install a browser on the server then forward X connections, rather than maintaining a local hosts file or modifying local DNS to catch and resolve local cluster queries:

ssh -X user@server 

Success \o/

For detailed kcli documentation see: https://kcli.readthedocs.io/en/latest/

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