K8S operator webhook error x509: certificate is not valid for any names

[qchenzi]

apps@(datamars)mlpl70855-10.18.106.234 crds$ kubectl apply -f quick-start.yaml
Error from server (InternalError): error when creating "quick-start.yaml": Internal error occurred: failed calling webhook "polardbxcluster-mutate.polardbx.aliyun.com": failed to call webhook: Post "https://polardbx-admission-webhook.polardbx-operator-system.svc:443/apis/admission.polardbx.aliyun.com/v1/mutate-polardbx-aliyun-com-v1-polardbxcluster?timeout=10s": x509: certificate is not valid for any names, but wanted to match polardbx-admission-webhook.polardbx-operator-system.svc

[qchenzi]

所示webhook服务的available状态为True

[vettalwu]

@qchenzi It seems that Kubernetes API server is unable to verify the webhook's TLS certificate. Do you use cert manager or a self generated cert file? Please find it and check the cert info by following command:

openssl x509 -in webhook-certificate.crt -text -noout

[qchenzi]

Hi @vettalwu ,

I've checked the TLS certificate using the openssl command, and it appears to be generated for the hostname polardbx-admission-webhook.polardbx-operator-system.svc, which matches the required hostname for the webhook service. Here are the details from the certificate:

• Issuer: CN=polardbx-admission-webhook.polardbx-operator-system.svc
• Subject: CN=polardbx-admission-webhook.polardbx-operator-system.svc

Despite the certificate seemingly correctly configured, I'm still encountering the x509 certificate error when applying configurations via kubectl. Do you have any suggestions on what steps I should take next to resolve this?
Thank you for your assistance.

[vettalwu]

@qchenzi Can you try to restart the api-server? K8s api-server may create a self-generated certificate, which may be invalid. Refer to: kubernetes/kubernetes#86552.

[qchenzi]

Hi @vettalwu ,

I've restarted the api-server as you suggested, but the issue persists with the x509: certificate is not valid for any names error still occurring. Here are the steps I've taken:

1. Restarted the Kubernetes api-server.
2. retry to apply *.yaml file
   

Could there be other diagnostic steps to attempt? Or is there a possibility of a different configuration causing the certificate validation issue?

Thank you for your assistance!

[vettalwu]

@qchenzi Check the apiserver ca using following command:

eplace {Master_IP} with your master IP and 6443 with your apiserver port
curl --resolve apiserver-loopback-client:6443:{Master_IP} -k -v https://apiserver-loopback-client:6443/healthz