docs/doc/source/security/kubernetes/configure-docker-registry-certificate-after-installation-c519edbfe90a.rst

Configure Docker Registry Certificate

The local Docker registry provides secure HTTPS access using the registry API.

By default, a self-signed server certificate is generated at installation time for the registry API. For more secure access, an intermediate or Root CA-signed server certificate is strongly recommended.

To configure or update the HTTPS certificate for the local Docker registry, create a certificate named system-registry-local-certificate in the deployment namespace. The secretName attribute of this certificate's spec must also be named system-registry-local-certificate.

See the example procedure below for creating the certificate for the local Docker registry.

Update the following fields:

• The duration and renewBefore dates for the expiry and renewal times you desire. The system will automatically renew and re-install the certificate.
• The subject fields to identify your particular system.
• The ipAddresses with the Floating IP Address and the MGMT Floating IP address for this system which MUST be specified for this certificate. Use the system addrpool-list command to get the floating IP Address and MGMT floating IP Address for your system.
• The dnsNames with registry.local, registry.central and any names configured for this system's Floating IP Address in an external DNS server.

1. Create the Docker certificate yaml configuration file.

   ~(keystone_admin)]$ cat <<EOF > docker-certificate.yaml
   ---
   apiVersion: cert-manager.io/v1
   kind: Certificate
   metadata:
     name: system-registry-local-certificate
     namespace: deployment
   spec:
     secretName: system-registry-local-certificate
     issuerRef:
       name: system-local-ca
       kind: ClusterIssuer
     duration: 2160h    # 90d
     renewBefore: 360h  # 15d
     subject:
       organizationalUnits:
         - StarlingX-system-registry-local
     ipAddresses:
       - <OAM_FLOATING_IP>
       - <MGMT_FLOATING_IP>
     dnsNames:
       - registry.local
       - registry.central
       - <external-FQDN-for-OAM-Floating-IP-Address, if applicable>

2. Apply the configuration.

   ~(keystone_admin)]$ kubectl apply -f docker-certificate.yaml

3. Verify the configuration.

   ~(keystone_admin)]$ kubectl get certificate system-registry-local-certificate -n deployment

   If configuration was successful, the certificate's Ready status will be True.

4. Update the platform's trusted certificates (i.e. ssl_ca) with the Root associated with system-registry-local-certificate.

   See the example below where a Root system-local-ca was used to sign the system-registry-local-certificate, the ca.crt of the system-local-ca SECRET is extracted and added as a trusted for (i.e. system certificate-install -m ssl_ca).

   ~(keystone_admin)]$ kubectl -n cert-manager get secret system-local-ca -o yaml | fgrep tls.crt | awk '{print $2}' | base64 --decode >> system-local-ca.pem
   ~(keystone_admin)]$ system certificate-install -m ssl_ca system-local-ca.pem

The Docker registry certificate installation is now complete, and Cert-Manager will handle the lifecycle management of the certificate.

Limitations for using IPv6 addresses related to management and OAM networks