Bootstrapping cert-manager

The issuer defined in the cert-manager application uses the DNS solver. The advantage of the DNS solver is that it works behind firewalls and can provision certificates for environments not exposed to the Internet, such as the Tucson teststand. The DNS solver uses an AWS service user with write access to Route 53 to answer Let’s Encrypt challenges.

In order to use cert-manager, you must be hosting the DNS for the external hostname of the Science Platform installation in AWS Route 53. See Hostnames and TLS for more information.

First, ensure that cert-manager is set up for the domain in which the cluster will be hosted. If this is a new domain, follow the instructions in Setting up Route 53 for cert-manager.

Then, in Route 53, create a CNAME from _acme-challenge.<cluster-name> to _acme-challenge.tls.<domain> where <domain> is the domain in which the cluster is located (such as lsst.codes or lsst.cloud). The new Route 53 dialog box makes this very confusing to do in the console. Select CNAME from the lower drop-down menu and then IP address or other value from the top drop-down menu, and then you can enter _acme-challenge.tls.lsst.codes (for example) as the CNAME target.

For example, if the cluster name is data-dev.lsst.cloud, create a CNAME record at _acme-challenge.data-dev.lsst.cloud whose value is _acme-challenge.tls.lsst.cloud. In the Route 53 console, the name of the record you create in the lsst.cloud hosted zone will be _acme-challenge.data-dev (yes, including the period).

Add the following to the values-*.yaml file for an environment:

config:
  route53:
    awsAccessKeyId: "<access-key>"
    hostedZone: "<hosted-zone>"

<access-key> and <hosted-zone> must correspond to the domain under which the cluster is hosted. The values for the two most common Rubin Science Platform domains are:

lsst.codes:
  awsAccessKeyId: "AKIAQSJOS2SFLUEVXZDB"
  hostedZone: "Z06873202D7WVTZUFOQ42"
lsst.cloud:
  awsAccessKeyId: "AKIAQSJOS2SFKQBMDRGR"
  hostedZone: "Z0567328105IEHEMIXLCO"

This key ID is for an AWS service user that has write access to the tls subdomain of the domain in which the cluster is hosted, and therefore can answer challenges.

Finally, store the secret key for this AWS access key in Vault as the cert-manager secret for that cluster. The Vault secret should look something like this:

data:
  aws-access-key-id: "<access-key>"
  aws-secret-access-key: "<secret>"

The secrets for the SQuaRE-maintained Rubin Science Platform domains are stored in 1Password (search for cert-manager-lsst-codes or cert-manager-lsst-cloud). If this cluster is in the same domain as another, working cluster, you can copy the secret from that cluster into the appropriate path for the new cluster.