Local Registry Server Certificates

For the Local Docker Registry, HTTPS is always enabled. By default, a self-signed server certificate and key is generated and installed for this endpoint. However, it is strongly recommended that you update the server certificate used after installation with an Intermediate or Root CA-signed server certificate and key. Refer to the documentation for the external Intermediate or Root CA that you are using, on how to create public certificate and private key pairs, signed by a Root CA, for HTTPS.

The local Docker registry provides Docker image service that can be accessed using the registry API by secure HTTPS. Standalone system, central cloud and every subcloud of DC system has their own Docker registry called registry.local.

The Docker registry on the central cloud of DC system has an alias of registry.central, which is used by subcloud to remotely login or pull images from this central Docker registry.

About this task

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

The Intermediate or Root CA-signed certificate for the registry must have at least the following SANs: DNS:registry.local, DNS:registry.central, IP Address:<oam-floating-ip-address>, IP Address:<mgmt-floating-ip-address>. Use the system addrpool-list command to get the OAM floating IP Address and management floating IP Address for your system. You can add any additional DNS entry(s) that you have set up for your OAM floating IP Address.

Use the following procedure to install an intermediate or Root CA-signed certificate to either replace the default self-signed certificate or to replace an expired or soon to expire certificate.

Prerequisites

Obtain an intermediate or Root CA-signed certificate and key from a trusted Intermediate or Root CA. Refer to the documentation for the external Root CA that you are using, on how to create public certificate and private key pairs, signed by an Intermediate or Root CA, for HTTPS.

For lab purposes, see Create Certificates Locally using openssl for how to create a test Intermediate or Root CA certificate and key, and use it to sign test certificates.

Put the PEM encoded versions of the certificate and key in a single file, and copy the file to the controller host.

Also, obtain the certificate of the Intermediate or Root CA that signed the above certificate.

Procedure

  1. In order to enable internal use of the Docker registry certificate, update the trusted CA list for this system with the Root CA associated with the Docker registry certificate.

    ~(keystone_admin)]$ system certificate-install --mode ssl_ca
    <pathTocertificate>
    

    where:

    <pathTocertificate>

    is the path to the intermediate or Root CA certificate associated with the Docker registry’s Intermediate or Root CA-signed certificate.

  2. Update the Docker registry certificate using the certificate-install command.

    Set the mode (-m or --mode) parameter to docker_registry.

    ~(keystone_admin)]$ system certificate-install --mode docker_registry
    <pathTocertificateAndKey>
    

    where:

    <pathTocertificateAndKey>

    is the path to the file containing both the Docker registry’s Intermediate or Root CA-signed certificate and private key to install.

Refer to Install/Update Local Registry Certificates on how to install/update and renew local registry certificates.