4.4. Troubleshooting custom certificates

Procedure

1. From MicroShift, ensure that the certificate is served by the kube-apiserver and verify that the certificate path is appended to the --tls-sni-cert-key FLAG by running the following command:

   $ journalctl -u microshift -b0 | grep tls-sni-cert-key

   Example output

   Jan 24 14:53:00 localhost.localdomain microshift[45313]: kube-apiserver I0124 14:53:00.649099   45313 flags.go:64] FLAG: --tls-sni-cert-key="[/home/eslutsky/dev/certs/server.crt,/home/eslutsky/dev/certs/server.key;/var/lib/microshift/certs/kube-apiserver-external-signer/kube-external-serving/server.crt,/var/lib/microshift/certs/kube-apiserver-external-signer/kube-external-serving/server.key;/var/lib/microshift/certs/kube-apiserver-localhost-signer/kube-apiserver-localhost-serving/server.crt,/var/lib/microshift/certs/kube-apiserver-localhost-signer/kube-apiserver-localhost-serving/server.key;/var/lib/microshift/certs/kube-apiserver-service-network-signer/kube-apiserver-service-network-serving/server.crt,/var/lib/microshift/certs/kube-apiserver-service-network-signer/kube-apiserver-service-network-serving/server.key

2. From the client, ensure that the kube-apiserver is serving the correct certificate by running the following command:

   $ openssl s_client -connect <SNI_ADDRESS>:6443 -showcerts | openssl x509 -text -noout -in - | grep -C 1 "Alternative\|CN"