===================== Get Certbot ===================== .. contents:: Table of Contents :local: About Certbot ============= Certbot is packaged for many common operating systems and web servers. Check whether ``certbot`` (or ``letsencrypt``) is packaged for your web server's OS by visiting certbot.eff.org_, where you will also find the correct installation instructions for your system. .. Note:: Unless you have very specific requirements, we kindly suggest that you use the Certbot packages provided by your package manager (see certbot.eff.org_). If such packages are not available, we recommend using ``certbot-auto``, which automates the process of installing Certbot on your system. .. _certbot.eff.org: https://certbot.eff.org System Requirements =================== Certbot currently requires Python 2.6, 2.7, or 3.3+. By default, it requires root access in order to write to ``/etc/letsencrypt``, ``/var/log/letsencrypt``, ``/var/lib/letsencrypt``; to bind to ports 80 and 443 (if you use the ``standalone`` plugin) and to read and modify webserver configurations (if you use the ``apache`` or ``nginx`` plugins). If none of these apply to you, it is theoretically possible to run without root privileges, but for most users who want to avoid running an ACME client as root, either `letsencrypt-nosudo `_ or `simp_le `_ are more appropriate choices. The Apache plugin currently requires an OS with augeas version 1.0; currently `it supports `_ modern OSes based on Debian, Fedora, SUSE, Gentoo and Darwin. Installing with ``certbot-auto`` requires 512MB of RAM in order to build some of the dependencies. Installing from pre-built OS packages avoids this requirement. You can also temporarily set a swap file. See "Problems with Python virtual environment" below for details. Alternate installation methods ================================ If you are offline or your operating system doesn't provide a package, you can use an alternate method for installing ``certbot``. .. _certbot-auto: Certbot-Auto ------------ The ``certbot-auto`` wrapper script installs Certbot, obtaining some dependencies from your web server OS and putting others in a python virtual environment. You can download and run it as follows:: user@webserver:~$ wget https://dl.eff.org/certbot-auto user@webserver:~$ chmod a+x ./certbot-auto user@webserver:~$ ./certbot-auto --help .. hint:: The certbot-auto download is protected by HTTPS, which is pretty good, but if you'd like to double check the integrity of the ``certbot-auto`` script, you can use these steps for verification before running it:: user@server:~$ wget -N https://dl.eff.org/certbot-auto.asc user@server:~$ gpg2 --recv-key A2CFB51FA275A7286234E7B24D17C995CD9775F2 user@server:~$ gpg2 --trusted-key 4D17C995CD9775F2 --verify certbot-auto.asc certbot-auto The ``certbot-auto`` command updates to the latest client release automatically. Since ``certbot-auto`` is a wrapper to ``certbot``, it accepts exactly the same command line flags and arguments. For more information, see `Certbot command-line options `_. For full command line help, you can type:: ./certbot-auto --help all Problems with Python virtual environment ---------------------------------------- On a low memory system such as VPS with less than 512MB of RAM, the required dependencies of Certbot will failed to build. This can be identified if the pip outputs contains something like ``internal compiler error: Killed (program cc1)``. You can workaround this restriction by creating a temporary swapfile:: user@webserver:~$ sudo fallocate -l 1G /tmp/swapfile user@webserver:~$ sudo chmod 600 /tmp/swapfile user@webserver:~$ sudo mkswap /tmp/swapfile user@webserver:~$ sudo swapon /tmp/swapfile Disable and remove the swapfile once the virtual enviroment is constructed:: user@webserver:~$ sudo swapoff /tmp/swapfile user@webserver:~$ sudo rm /tmp/swapfile 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 your webserver from inside the Docker container. Most users should use the operating system packages (see instructions at certbot.eff.org_) or, as a fallback, ``certbot-auto``. You should only use Docker if you are sure you know what you are doing and have a good reason to do so. You should definitely read the :ref:`where-certs` section, in order to know how to manage the certs manually. `Our ciphersuites page `__ provides some information about recommended ciphersuites. If none of these make much sense to you, you should definitely use the certbot-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 certbot \ -v "/etc/letsencrypt:/etc/letsencrypt" \ -v "/var/lib/letsencrypt:/var/lib/letsencrypt" \ certbot/certbot certonly Running Certbot with the ``certonly`` command will obtain a certificate and place it in the directory ``/etc/letsencrypt/live`` on your system. Because Certonly cannot install the certificate from within Docker, you must install the certificate manually according to the procedure recommended by the provider of your webserver. For more information about the layout of the ``/etc/letsencrypt`` directory, see :ref:`where-certs`. .. _Docker: https://docker.com .. _`install Docker`: https://docs.docker.com/engine/installation/ Operating System Packages ------------------------- **Arch Linux** .. code-block:: shell sudo pacman -S certbot **Debian** If you run Debian Stretch or Debian Sid, you can install certbot packages. .. code-block:: shell sudo apt-get update sudo apt-get install certbot python-certbot-apache If you don't want to use the Apache plugin, you can omit the ``python-certbot-apache`` package. Packages exist for Debian Jessie via backports. First you'll have to follow the instructions at http://backports.debian.org/Instructions/ to enable the Jessie backports repo, if you have not already done so. Then run: .. code-block:: shell sudo apt-get install certbot python-certbot-apache -t jessie-backports **Fedora** .. code-block:: shell sudo dnf install certbot python2-certbot-apache **FreeBSD** * Port: ``cd /usr/ports/security/py-certbot && make install clean`` * Package: ``pkg install py27-certbot`` **Gentoo** The official Certbot client is available in Gentoo Portage. If you want to use the Apache plugin, it has to be installed separately: .. code-block:: shell emerge -av app-crypt/certbot emerge -av app-crypt/certbot-apache When using the Apache plugin, you will run into a "cannot find a cert or key directive" error if you're sporting the default Gentoo ``httpd.conf``. You can fix this by commenting out two lines in ``/etc/apache2/httpd.conf`` as follows: Change .. code-block:: shell LoadModule ssl_module modules/mod_ssl.so to .. code-block:: shell # LoadModule ssl_module modules/mod_ssl.so # For the time being, this is the only way for the Apache plugin to recognise the appropriate directives when installing the certificate. Note: this change is not required for the other plugins. **NetBSD** * Build from source: ``cd /usr/pkgsrc/security/py-certbot && make install clean`` * Install pre-compiled package: ``pkg_add py27-certbot`` **OpenBSD** * Port: ``cd /usr/ports/security/letsencrypt/client && make install clean`` * Package: ``pkg_add letsencrypt`` **Other Operating Systems** OS packaging is an ongoing effort. If you'd like to package Certbot for your distribution of choice please have a look at the :doc:`packaging`. Installing 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 Certbot team!