OpenShift Cheatsheet
Here some helpful OpenShift commands which work (at least) since version >= 4.11
How to get a token: https://oauth-openshift.apps.ocp.example.com/oauth/token/display
You might need it for login or automatization.
Switch namespace:
$ oc project <namespace>
quit namespace:
$ oc project -n default
Get all resources:
$ oc get all
Get status of all nodes:
$ oc get nodes
Show Uptime:
$ oc get machines -A
Sort Events by time:
$ oc get events --sort-by=metadata.creationTimestamp
Show/edit initial configuration:
$ oc get cm cluster-config-v1 -o yaml -n kube-system (edit)
Information gathering: https://docs.openshift.com/container-platform/4.12/cli_reference/openshift_cli/administrator-cli-commands.html#oc-adm-inspect (evtl. secrets löschen!)
List alerts:
$ oc -n openshift-monitoring exec -ti alertmanager-main-0 -c alertmanager -- amtool alert --alertmanager.url=http://localhost:9093 -o extended
Patch resource:
$ oc patch installplan install-defgh -n openshift-operators-redhat --type merge --patch '{"spec":{"approved":true}}'
Liveness/Readiness Probes of all pods in certain timestamp:
$ oc adm node-logs --role worker -u kubelet | egrep -E 'Liveness|Readiness' | grep "Aug 21 11:22"
Useful terms
IPI Installer-provisioned infrastructure cluster
Cluster installed by install command; user must only provide some information (which platform, cluster name, network, storage, ...)
UPI User provisioned infrastructure cluster
- DNS and Loadbalancing must already be there
- Installation manually, download ova file (in case of vSphere)
- master created manually
- workers recommended
- *no* keepalived
Advantages:
IPI: installation more simple, using preconfigured features
UPI: more flexibility, no loadbalancer outage during update
Change from IPI -> UPI not possible
| cm | config map |
| csv | cluster service version |
| dc | deploymentconfig |
| ds | deploymentsetting |
| ip | installplan |
| mcp | machineconfigpool |
| pv | persistent volume |
| sa | service account |
| scc | security context constraints |
| svc | service |