Grafana cannot validate certificate for *.*.*.* because it doesn't contain any IP SANs"

I am testing Grafana v6.2.2, want to accecss GUI using keycloak SSO, not username/password.
I created a kubectl secret including a certificate, and on Grafana values.yaml to use this secret.

After Grafana deployed, on Grafana GUI, there is button to access with keycloak realm, but can’t access success.
In Grafana container cpro-grafana logs, there are Error, "2019-08-21T07:54:33+0000 lvl=eror msg=login.OAuthLogin(NewTransportWithCode) logger=context userId=0 orgId=0 uname= error=“Post x509: cannot validate certificate for because it doesn’t contain any IP SANs”

But in fact, there is IP SANS “value is” in this certificate.

My questions:
(1) For certificate, SANs is not required field, it is extention field. That means SANs is not included in some certificate. Why SANs is required when Grafana validate certificate?
(2) Because IP SANS "value is"is in the certificate, log “cannot validate certificate for because it doesn’t contain any IP SANs” means this IP address is not valid?

Thank you for your reply!

The solution for my grafana has been

Add skip_verify = true on /etc/grafana/grafana.ini and restart service

Sorry for my awful english

The above solution is not working to me I too having the same issue
Any other solution for that

Yes it’s not skip_verify there is an option already present in the Outh like tls_skip_verify=false it should be in true to avoid that error