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.git
Upgrading from previous versions
sudo 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 letsencrypt:set myapp email firstname.lastname@example.org -----> Setting email to email@example.com $ 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 letsencrypt:set --global email firstname.lastname@example.org
Automatic certificate renewal
To enable the automatic renewal of certificates, a cronjob needs to be defined for
dokku user which will run daily and renew any certificates that are due to
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:
||(none)||The name of a valid lego dns-provider|
|(none)||REQUIRED: E-mail address to use for registering with Let's Encrypt.|
||2592000 (30 days)||Time in seconds left on a certificate before it should get renewed|
||(none)||Extra arguments to pass via
||default||Which ACME server to use. Can be 'default', 'staging' or a URL|
You can set a setting using
dokku letsencrypt:set $APP $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
Note: See "DNS-01 Challenge" for more information on configuration a dns-provider for DNS-01 based challenges and wildcard support.
Redirecting from HTTP to HTTPS
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 to
- 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
Dockerfile and Image-based Deploys
When securing Dockerfile and Image-based deploys with dokku-letsencrypt, be aware of the proxy mechanism for dokku 0.6+.
For Dockerfile deploys - as well as those via
git:from-image - 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/Image-based deployment (where the app is listening on port 5555) with dokku-letsencrypt would be:
- Create a new app
myappin dokku and push to the
email@example.com. 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.
Dealing with rate limit
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
dokku-letsencrypt on all your applications would create a certificate for each application subdomain on
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
dokku domains:add foo foo.com dokku domains:remove foo foo.dokku.example.com dokku letsencrypt:enable foo
While playing around with this plugin, you might want to switch to the let's encrypt staging server by running
dokku letsencrypt:set myapp server staging to enjoy much higher rate limits and switching back to the real server by running
dokku letsencrypt:set myapp server once you are ready.
Generating a Cert for multiple domains
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-default
Functionality sponsored by Orca Scan Ltd.
In order to provide a Letsencrypt certificate for a wildcard domain, a DNS-01 challenge must be used. To configure, the
dns-provider property must be set to a supported Lego provider. Additionally, the environment variables used by the DNS provider must be set as letsencrypt properties with the prefix
dns-provider-. Both global and app-specific properties are supported.
Warning: Before using a DNS-based challenge, ensure all DNS records - including wildcard records - are pointing at your server.
# set the provider to namecheap dokku letsencrypt:set --global dns-provider namecheap # set the properties necessary for namecheap usage dokku letsencrypt:set --global dns-provider-NAMECHEAP_API_USER user dokku letsencrypt:set --global dns-provider-NAMECHEAP_API_KEY key
Due to limitations in how certain DNS providers work, environment variables must not use the
_FILE based method for referring to values in files.
Please see the Lego documentation for your DNS provider for more information on what configuration is necessary to utilize DNS-01 challenges.
dokku 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.