dokku-letsencrypt is the official plugin for dokku that gives the ability to automatically retrieve and install TLS certificates from letsencrypt.org. During ACME validation, your app will stay available at any time.
By running this plugin, you agree to the Let's Encrypt Subscriber Agreement automatically (because prompting you whether you agree might break running the plugin as part of a cronjob).
If you like Let's Encrypt, please consider donating to Let's Encrypt.
sudo dokku plugin:install https://github.com/dokku/dokku-letsencrypt.gitsudo dokku plugin:update letsencrypt$ dokku letsencrypt:help
letsencrypt:active <app> Verify if letsencrypt is active for an app
letsencrypt:auto-renew Auto-renew all apps secured by letsencrypt if renewal is necessary
letsencrypt:auto-renew <app> Auto-renew app if renewal is necessary
letsencrypt:cleanup <app> Cleanup stale certificates and configurations
letsencrypt:cron-job <--add|--remove> Add or remove an auto-renewal cronjob
letsencrypt:disable <app> Disable letsencrypt for an app
letsencrypt:enable <app> Enable or renew letsencrypt for an app
letsencrypt:list List letsencrypt-secured apps with certificate expiry
letsencrypt:revoke <app> Revoke letsencrypt certificate for app
If using this plugin with Cloudflare:
- The domain dns should be setup in "Proxied" mode
- SSL/TLS mode must be in "Full" mode
- Using letsencrypt in "Flexible" mode will cause Cloudflare to detect your server as down
- Using "Full" mode will require disabling SSL/TLS in cloudflare in order to renew the certificate.
If using "Flexible" SSL/TLS mode, avoid using this plugin.
See these two links for more details:
The app which is obtaining a letsencrypt certificate must already be deployed and accessible over the internet (i.e. in the browser) in order to add letsencrypt to your app. This plugin will fail to apply for an app that has otherwise only been created.
Obtain a Let's encrypt TLS certificate for app myapp (you can also run this command to renew the certificate):
$ dokku config:set --no-restart myapp DOKKU_LETSENCRYPT_EMAIL=your@email.tld
-----> Setting config vars
DOKKU_LETSENCRYPT_EMAIL: your@email.tld
$ dokku letsencrypt:enable myapp
=====> Let's Encrypt myapp...
-----> Updating letsencrypt docker image...
latest: Pulling from dokku/letsencrypt
Digest: sha256:20f2a619795c1a3252db6508f77d6d3648ad5b336e67caaf801126367dbdfa22
Status: Image is up to date for dokku/letsencrypt:latest
done
-----> Enabling letsencrypt proxy for myapp...
-----> Getting letsencrypt certificate for myapp...
- Domain 'myapp.mydomain.com'
[ removed various log messages for brevity ]
-----> Certificate retrieved successfully.
-----> Symlinking let's encrypt certificates
-----> Configuring SSL for myapp.mydomain.com...(using /var/lib/dokku/plugins/available/nginx-vhosts/templates/nginx.ssl.conf.template)
-----> Creating https nginx.conf
-----> Running nginx-pre-reload
Reloading nginx
-----> Disabling letsencrypt proxy for myapp...
done
Once the certificate is installed, you can use the certs:* built-in commands to edit and query your certificate.
You could also use the following command to set an email address for global. So you don't need to type the email address for different application.
dokku config:set --global DOKKU_LETSENCRYPT_EMAIL=your@email.tld
To enable the automatic renewal of certificates, a cronjob needs to be defined for
the dokku user which will run daily and renew any certificates that are due to
be renewed.
This can be done using the following command:
dokku letsencrypt:cron-job --add
dokku-letsencrypt uses the Dokku environment variable manager for all configuration. The important environment variables are:
| Variable | Default | Description |
|---|---|---|
DOKKU_LETSENCRYPT_EMAIL |
(none) | REQUIRED: E-mail address to use for registering with Let's Encrypt. |
DOKKU_LETSENCRYPT_GRACEPERIOD |
2592000 (30 days) | Time in seconds left on a certificate before it should get renewed |
DOKKU_LETSENCRYPT_SERVER |
default | Which ACME server to use. Can be 'default', 'staging' or a URL |
DOKKU_LETSENCRYPT_ARGS |
(none) | Extra arguments to pass via docker run. See the lego CLI documentation for available options. |
You can set a setting using dokku config:set --no-restart <myapp> SETTING_NAME=setting_value. When looking for a setting, the plugin will first look if it was defined for the current app and fall back to settings defined by --global.
Dokku's default nginx template will automatically redirect HTTP requests to HTTPS when a certificate is present.
You can customize the nginx template if you want different behaviour.
dokku-letsencrypt gets around having to disable your web server using the following workflow:
- Temporarily add a reverse proxy for the
/.well-known/path of your app tohttps://127.0.0.1:$ACMEPORT - Run the acme/lego Let's Encrypt client in a Docker container binding to
$ACMEPORTto complete the ACME challenge and retrieve the TLS certificates - Install the TLS certificates
- Remove the reverse proxy and reload nginx
For a more in-depth explanation, see this blog post
When securing Dockerfile deploys with dokku-letsencrypt, be aware of the proxy mechanism for dokku 0.6+.
For Dockerfile deploys, by default, dokku will determine which ports a container exposes and proxies all those exposed ports in the Docker container by listening on the same port numbers on the host. This means that both the proxies for HTTP port 80 and HTTPS port 443 to the app's container need to be manually configured using the dokku proxy:ports-* commands in order for certificate validation and browsing to the app via HTTPS to work.
A full workflow for creating a new Dockerfile deployment (where the app is listening on port 5555) with dokku-letsencrypt would be:
- Create a new app
myappin dokku and push to thedokku@myhost.comremote. This guide assumes that the Docker container will be listening for connections on port 5555 so replace container port numbers accordingly if necessary. - On the dokku host, use
dokku proxy:ports-add myapp http:80:5555to proxy HTTP port 80 to port 5555 on the Docker image - On the dokku host, use
dokku letsencrypt:enable myappto retrieve HTTPS certificates. - On the dokku host, use
dokku proxy:ports-add myapp https:443:5555to proxy HTTPS port 443 to port 5555 on the Docker image - (optional) On the dokku host, use
dokku proxy:ports-remove myapp http:5555:5555to remove a potential leftover proxy that was automatically configured on first deploy.
After these steps, the output of dokku proxy:ports myapp should look like this:
-----> Port mappings for myapp
-----> scheme host port container port
http 80 5555
https 443 5555
Replace the container port (5555 in the above example) with the port your app is listening on.
Note: Step 2 and step 4 cannot be joined together since a configured HTTPS proxy will include a ssl_certificate line in the app's nginx config that will cause nginx config validation to fail because no valid HTTPS certificate is available until step 3 is completed.
Be aware that Let's Encrypt is subject to rate limiting. The limit about the number of certificates you can add on a domain per week is a concern for dokku because of the default domain added to your new applications, named like <app>.<dokku-domain>: using dokku-letsencrypt on all your applications would create a certificate for each application subdomain on <dokku-domain>.
As a workaround, if you want to encrypt many applications, make sure to add a proper domain for each one and remove their default domain before running dokku-letsencrypt. For example, if your dokku domain is dokku.example.com and you want to encrypt your foo app:
dokku domains:add foo foo.com
dokku domains:remove foo foo.dokku.example.com
dokku letsencrypt:enable fooWhile playing around with this plugin, you might want to switch to the let's encrypt staging server by running dokku config:set --no-restart myapp DOKKU_LETSENCRYPT_SERVER=staging to enjoy much higher rate limits and switching back to the real server by running dokku config:unset --no-restart myapp DOKKU_LETSENCRYPT_SERVER once you are ready.
Your default dokku app is accessible under the root domain too. So if you have an application 00-default that is running under 00-default.mydomain.com it is accessible under mydomain.com too. Now if you enable letsencrypt for your 00-default application, it is not accessible anymore on mydomain.com. You can add the root domain to your dokku domains by typing:
dokku domains:add 00-default mydomain.com
dokku letsencrypt:enable 00-defaultdokku letsencrypt:enable <app> enables letsencrypt for an application or renews the certificate. This may lead to hitting rate limits with letsencrypt.
To avoid renewals, for example in a continuous deployment scenario, you could first check if letsencrypt has already been enabled for the app:
dokku letsencrypt:active <app> || dokku letsencrypt:enable <app>This plugin is released under the MIT license. See the file LICENSE.