certbot is a cli that enable you to get a free ssl cert for your site.

Install

sudo apt install certbot python3-certbot-dns-linode

Get linode key

Get your linode key from account settings with domain permission. Save the file as linode.ini

dns_linode_key = abcd
dns_linode_version = 4

Get cert

Be aware that juju.one is not the same as *.juju.one domain. To get one cert for all your domain, you have to pass two domain parameters -d juju.one -d *.juju.one

Here's the command to get cert for linode and domain.

certbot certonly --dns-linode --dns-linode-credentials linode.ini -d juju.one -d *.juju.one