报错：
rancher-rke-01:~/rke/rancher-helm/rancher # helm install rancher rancher-stable/rancher --namespace cattle-system --set hostname=www.rancher.local
Error: INSTALLATION FAILED: Internal error occurred: failed calling webhook "webhook.cert-manager.io": failed to call webhook: Post "https://cert-manager-webhook.cert-manager.svc:443/mutate?timeout=10s": context deadline exceeded
解决办法：
cert-manager 🚀 - 发生内部错误：调用webhook“ webhook.cert-manager.io”失败：发布https：//cert-manager-webhook.cert-manager.svc：443 / mutate？timeout = 30s：net / http：TLS握手超时 | bleepcoder.com
$ helm install \
cert-manager jetstack/cert-manager \
--namespace cert-manager \
--version v0.16.0 \
--set installCRDs=true
$ kubectl delete mutatingwebhookconfiguration.admissionregistration.k8s.io cert-manager-webhook
$ kubectl delete validatingwebhookconfigurations.admissionregistration.k8s.io cert-manager-webhook