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: $ kubectl krew install cert-manager For offline installation, download the binary and move it to /usr/local/bin:

$ 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

Manual certificate update

Check the next renewal time of a certificate:

$ kubectl cert-manager status certificate -n jenkins jenkins.jiaxzeng.com-tls

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

Trigger a manual renewal:

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

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.