========== User Guide ========== .. contents:: Table of Contents :local: .. _installation: Installation ============ .. _letsencrypt-auto: letsencrypt-auto ---------------- ``letsencrypt-auto`` is a wrapper which installs some dependencies from your OS standard package repositories (e.g using `apt-get` or `yum`), and for other dependencies it sets up a virtualized Python environment with packages downloaded from PyPI [#venv]_. It also provides automated updates. Firstly, please `install Git`_ and run the following commands: .. code-block:: shell git clone https://github.com/letsencrypt/letsencrypt cd letsencrypt .. _`install Git`: https://git-scm.com/book/en/v2/Getting-Started-Installing-Git .. note:: On RedHat/CentOS 6 you will need to enable the EPEL_ repository before install. .. _EPEL: http://fedoraproject.org/wiki/EPEL To install and run the client you just need to type: .. code-block:: shell ./letsencrypt-auto .. hint:: During the beta phase, Let's Encrypt enforces strict rate limits on the number of certificates issued for one domain. It is recommended to initially use the test server via `--test-cert` until you get the desired certificates. Throughout the documentation, whenever you see references to ``letsencrypt`` script/binary, you can substitute in ``letsencrypt-auto``. For example, to get basic help you would type: .. code-block:: shell ./letsencrypt-auto --help or for full help, type: .. code-block:: shell ./letsencrypt-auto --help all ``letsencrypt-auto`` is the recommended method of running the Let's Encrypt client beta releases on systems that don't have a packaged version. Debian, Arch linux and FreeBSD now have native packages, so on those systems you can just install ``letsencrypt`` (and perhaps ``letsencrypt-apache``). If you'd like to run the latest copy from Git, or run your own locally modified copy of the client, follow the instructions in the :doc:`contributing`. Some `other methods of installation`_ are discussed below. Plugins ======= The Let's Encrypt client supports a number of different "plugins" that can be used to obtain and/or install certificates. Plugins that can obtain a cert are called "authenticators" and can be used with the "certonly" command. Plugins that can install a cert are called "installers". Plugins that do both can be used with the "letsencrypt run" command, which is the default. =========== ==== ==== =============================================================== Plugin Auth Inst Notes =========== ==== ==== =============================================================== apache_ Y Y Automates obtaining and installing a cert with Apache 2.4 on Debian-based distributions with ``libaugeas0`` 1.0+. standalone_ Y N Uses a "standalone" webserver to obtain a cert. webroot_ Y N Obtains a cert by writing to the webroot directory of an already running webserver. manual_ Y N Helps you obtain a cert by giving you instructions to perform domain validation yourself. nginx_ Y Y Very experimental and not included in letsencrypt-auto_. =========== ==== ==== =============================================================== Future plugins for IMAP servers, SMTP servers, IRC servers, etc, are likely to be installers but not authenticators. Apache ------ If you're running Apache 2.4 on a Debian-based OS with version 1.0+ of the ``libaugeas0`` package available, you can use the Apache plugin. This automates both obtaining *and* installing certs on an Apache webserver. To specify this plugin on the command line, simply include ``--apache``. Standalone ---------- To obtain a cert using a "standalone" webserver, you can use the standalone plugin by including ``certonly`` and ``--standalone`` on the command line. This plugin needs to bind to port 80 or 443 in order to perform domain validation, so you may need to stop your existing webserver. To control which port the plugin uses, include one of the options shown below on the command line. * ``--standalone-supported-challenges http-01`` to use port 80 * ``--standalone-supported-challenges tls-sni-01`` to use port 443 Webroot ------- If you're running a webserver that you don't want to stop to use standalone, you can use the webroot plugin to obtain a cert by including ``certonly`` and ``--webroot`` on the command line. In addition, you'll need to specify ``--webroot-path`` or ``-w`` with the root directory of the files served by your webserver. For example, ``--webroot-path /var/www/html`` or ``--webroot-path /usr/share/nginx/html`` are two common webroot paths. If you're getting a certificate for many domains at once, each domain will use the most recent ``--webroot-path``. So for instance: ``letsencrypt certonly --webroot -w /var/www/example/ -d www.example.com -d example.com -w /var/www/eg -d eg.is -d www.eg.is`` Would obtain a single certificate for all of those names, using the ``/var/www/example`` webroot directory for the first two, and ``/var/www/eg`` for the second two. Note that to use the webroot plugin, your server must be configured to serve files from hidden directories. Manual ------ If you'd like to obtain a cert running ``letsencrypt`` on a machine other than your target webserver or perform the steps for domain validation yourself, you can use the manual plugin. While hidden from the UI, you can use the plugin to obtain a cert by specifying ``certonly`` and ``--manual`` on the command line. This requires you to copy and paste commands into another terminal session. Nginx ----- In the future, if you're running Nginx you can use this plugin to automatically obtain and install your certificate. The Nginx plugin is still experimental, however, and is not installed with letsencrypt-auto_. If installed, you can select this plugin on the command line by including ``--nginx``. Third party plugins ------------------- These plugins are listed at https://github.com/letsencrypt/letsencrypt/wiki/Plugins. If you're interested, you can also :ref:`write your own plugin `. Renewal ======= .. note:: Let's Encrypt CA issues short lived certificates (90 days). Make sure you renew the certificates at least once in 3 months. In order to renew certificates simply call the ``letsencrypt`` (or letsencrypt-auto_) again, and use the same values when prompted. You can automate it slightly by passing necessary flags on the CLI (see `--help all`), or even further using the :ref:`config-file`. The ``--renew-by-default`` flag may be helpful for automating renewal. If you're sure that UI doesn't prompt for any details you can add the command to ``crontab`` (make it less than every 90 days to avoid problems, say every month). Please note that the CA will send notification emails to the address you provide if you do not renew certificates that are about to expire. Let's Encrypt is working hard on automating the renewal process. Until the tool is ready, we are sorry for the inconvenience! .. _where-certs: Where are my certificates? ========================== First of all, we encourage you to use Apache or nginx installers, both which perform the certificate management automatically. If, however, you prefer to manage everything by hand, this section provides information on where to find necessary files. All generated keys and issued certificates can be found in ``/etc/letsencrypt/live/$domain``. Rather than copying, please point your (web) server configuration directly to those files (or create symlinks). During the renewal_, ``/etc/letsencrypt/live`` is updated with the latest necessary files. .. note:: ``/etc/letsencrypt/archive`` and ``/etc/letsencrypt/keys`` contain all previous keys and certificates, while ``/etc/letsencrypt/live`` symlinks to the latest versions. The following files are available: ``privkey.pem`` Private key for the certificate. .. warning:: This **must be kept secret at all times**! Never share it with anyone, including Let's Encrypt developers. You cannot put it into a safe, however - your server still needs to access this file in order for SSL/TLS to work. This is what Apache needs for `SSLCertificateKeyFile `_, and nginx for `ssl_certificate_key `_. ``cert.pem`` Server certificate only. This is what Apache < 2.4.8 needs for `SSLCertificateFile `_. ``chain.pem`` All certificates that need to be served by the browser **excluding** server certificate, i.e. root and intermediate certificates only. This is what Apache < 2.4.8 needs for `SSLCertificateChainFile `_. ``fullchain.pem`` All certificates, **including** server certificate. This is concatenation of ``chain.pem`` and ``cert.pem``. This is what Apache >= 2.4.8 needs for `SSLCertificateFile `_, and what nginx needs for `ssl_certificate `_. For both chain files, all certificates are ordered from root (primary certificate) towards leaf. Please note, that **you must use** either ``chain.pem`` or ``fullchain.pem``. In case of webservers, using only ``cert.pem``, will cause nasty errors served through the browsers! .. note:: All files are PEM-encoded (as the filename suffix suggests). If you need other format, such as DER or PFX, then you could convert using ``openssl``, but this means you will not benefit from automatic renewal_! .. _config-file: Configuration file ================== It is possible to specify configuration file with ``letsencrypt-auto --config cli.ini`` (or shorter ``-c cli.ini``). An example configuration file is shown below: .. include:: ../examples/cli.ini :code: ini By default, the following locations are searched: - ``/etc/letsencrypt/cli.ini`` - ``$XDG_CONFIG_HOME/letsencrypt/cli.ini`` (or ``~/.config/letsencrypt/cli.ini`` if ``$XDG_CONFIG_HOME`` is not set). .. keep it up to date with constants.py Getting help ============ If you're having problems you can chat with us on `IRC (#letsencrypt @ Freenode) `_ or get support on our `forums `_. If you find a bug in the software, please do report it in our `issue tracker `_. Remember to give us as much information as possible: - copy and paste exact command line used and the output (though mind that the latter might include some personally identifiable information, including your email and domains) - copy and paste logs from ``/var/log/letsencrypt`` (though mind they also might contain personally identifiable information) - copy and paste ``letsencrypt --version`` output - your operating system, including specific version - specify which installation_ method you've chosen Other methods of installation ============================= Running with Docker ------------------- Docker_ is an amazingly simple and quick way to obtain a certificate. However, this mode of operation is unable to install certificates or configure your webserver, because our installer plugins cannot reach it from inside the Docker container. You should definitely read the :ref:`where-certs` section, in order to know how to manage the certs manually. https://github.com/letsencrypt/letsencrypt/wiki/Ciphersuite-guidance provides some information about recommended ciphersuites. If none of these make much sense to you, you should definitely use the letsencrypt-auto_ method, which enables you to use installer plugins that cover both of those hard topics. If you're still not convinced and have decided to use this method, from the server that the domain you're requesting a cert for resolves to, `install Docker`_, then issue the following command: .. code-block:: shell sudo docker run -it --rm -p 443:443 -p 80:80 --name letsencrypt \ -v "/etc/letsencrypt:/etc/letsencrypt" \ -v "/var/lib/letsencrypt:/var/lib/letsencrypt" \ quay.io/letsencrypt/letsencrypt:latest auth and follow the instructions (note that ``auth`` command is explicitly used - no installer plugins involved). Your new cert will be available in ``/etc/letsencrypt/live`` on the host. .. _Docker: https://docker.com .. _`install Docker`: https://docs.docker.com/userguide/ Operating System Packages -------------------------- **FreeBSD** * Port: ``cd /usr/ports/security/py-letsencrypt && make install clean`` * Package: ``pkg install py27-letsencrypt`` **Arch Linux** .. code-block:: shell sudo pacman -S letsencrypt letsencrypt-apache **Debian** If you run Debian Stretch or Debian Sid, you can install letsencrypt packages. .. code-block:: shell sudo apt-get update sudo apt-get install letsencrypt python-letsencrypt-apache If you don't want to use the Apache plugin, you can ommit the ``python-letsencrypt-apache`` package. Packages for Debian Jessie are coming in the next few weeks. **Other Operating Systems** OS packaging is an ongoing effort. If you'd like to package Let's Encrypt client for your distribution of choice please have a look at the :doc:`packaging`. From source ----------- Installation from source is only supported for developers and the whole process is described in the :doc:`contributing`. .. warning:: Please do **not** use ``python setup.py install`` or ``python pip install .``. Please do **not** attempt the installation commands as superuser/root and/or without virtual environment, e.g. ``sudo python setup.py install``, ``sudo pip install``, ``sudo ./venv/bin/...``. These modes of operation might corrupt your operating system and are **not supported** by the Let's Encrypt team! Comparison of different methods ------------------------------- Unless you have a very specific requirements, we kindly ask you to use the letsencrypt-auto_ method. It's the fastest, the most thoroughly tested and the most reliable way of getting our software and the free SSL certificates! Beyond the methods discussed here, other methods may be possible, such as installing Let's Encrypt directly with pip from PyPI or downloading a ZIP archive from GitHub may be technically possible but are not presently recommended or supported. .. rubric:: Footnotes .. [#venv] By using this virtualized Python environment (`virtualenv `_) we don't pollute the main OS space with packages from PyPI!