Master Kubernetes Certificate Management with the kubectl cert-manager Plugin

Install cert-manager plugin

Use krew to install the

cert-manager

plugin. If krew is not installed, refer to the linked article. Run:

<code>$ kubectl krew install cert-manager</code>

For offline installation, download the binary and move it to

/usr/local/bin

:

<code>$ curl -L -o kubectl-cert-manager.tar.gz https://github.com/cert-manager/cert-manager/releases/download/v1.12.13/kubectl-cert_manager-linux-amd64.tar.gz
$ tar xzf kubectl-cert-manager.tar.gz -C /tmp
$ sudo mv /tmp/kubectl-cert_manager /usr/local/bin</code>

Manual certificate update

Check the next renewal time of a certificate:

<code>$ kubectl cert-manager status certificate -n jenkins jenkins.jiaxzeng.com-tls</code>

Tip: “Not After” shows the certificate expiration date; “Renewal Time” shows the automatic renewal schedule.

Trigger a manual renewal:

<code>$ kubectl cert-manager renew -n jenkins jenkins.jiaxzeng.com-tls
$ kubectl cert-manager status certificate -n jenkins jenkins.jiaxzeng.com-tls | grep Not</code>

After renewal, the “Not After” date moves forward.

Conclusion

As Kubernetes clusters grow, managing certificates manually becomes inefficient and error‑prone. The

kubectl cert-manager

plugin simplifies status inspection and troubleshooting, greatly improving operational efficiency.