synapse/INSTALL.md

• Installing Synapse
  • Installing from source
    • Platform-Specific Instructions
    • Troubleshooting Installation
  • Prebuilt packages
• Setting up Synapse
  • TLS certificates
  • Registering a user
  • Setting up a TURN server
  • URL previews

Installing Synapse

Installing from source

(Prebuilt packages are available for some platforms - see Prebuilt packages.)

System requirements:

• POSIX-compliant system (tested on Linux & OS X)
• Python 3.5, 3.6, 3.7, or 2.7
• At least 1GB of free RAM if you want to join large public rooms like #matrix:matrix.org

Synapse is written in Python but some of the libraries it uses are written in C. So before we can install Synapse itself we need a working C compiler and the header files for Python C extensions. See Platform-Specific Instructions for information on installing these on various platforms.

To install the Synapse homeserver run:

mkdir -p ~/synapse
virtualenv -p python3 ~/synapse/env
source ~/synapse/env/bin/activate
pip install --upgrade pip
pip install --upgrade setuptools
pip install matrix-synapse[all]

This will download Synapse from PyPI and install it, along with the python libraries it uses, into a virtual environment under ~/synapse/env. Feel free to pick a different directory if you prefer.

This Synapse installation can then be later upgraded by using pip again with the update flag:

source ~/synapse/env/bin/activate
pip install -U matrix-synapse[all]

Before you can start Synapse, you will need to generate a configuration file. To do this, run (in your virtualenv, as before)::

cd ~/synapse
python -m synapse.app.homeserver \
    --server-name my.domain.name \
    --config-path homeserver.yaml \
    --generate-config \
    --report-stats=[yes|no]

... substituting an appropriate value for --server-name. The server name determines the "domain" part of user-ids for users on your server: these will all be of the format @user:my.domain.name. It also determines how other matrix servers will reach yours for Federation. For a test configuration, set this to the hostname of your server. For a more production-ready setup, you will probably want to specify your domain (example.com) rather than a matrix-specific hostname here (in the same way that your email address is probably user@example.com rather than user@email.example.com) - but doing so may require more advanced setup. - see Setting up Federation. Beware that the server name cannot be changed later.

This command will generate you a config file that you can then customise, but it will also generate a set of keys for you. These keys will allow your Home Server to identify itself to other Home Servers, so don't lose or delete them. It would be wise to back them up somewhere safe. (If, for whatever reason, you do need to change your Home Server's keys, you may find that other Home Servers have the old key cached. If you update the signing key, you should change the name of the key in the <server name>.signing.key file (the second word) to something different. See the spec for more information on key management.)

You will need to give Synapse a TLS certficate before it will start - see TLS certificates.

To actually run your new homeserver, pick a working directory for Synapse to run (e.g. ~/synapse), and::

cd ~/synapse
source env/bin/activate
synctl start

Platform-Specific Instructions

Debian/Ubuntu/Raspbian

Installing prerequisites on Ubuntu or Debian:

sudo apt-get install build-essential python3-dev libffi-dev \
                     python-pip python-setuptools sqlite3 \
                     libssl-dev python-virtualenv libjpeg-dev libxslt1-dev

ArchLinux

Installing prerequisites on ArchLinux:

sudo pacman -S base-devel python python-pip \
               python-setuptools python-virtualenv sqlite3

CentOS/Fedora

Installing prerequisites on CentOS 7 or Fedora 25:

sudo yum install libtiff-devel libjpeg-devel libzip-devel freetype-devel \
                 lcms2-devel libwebp-devel tcl-devel tk-devel redhat-rpm-config \
                 python-virtualenv libffi-devel openssl-devel
sudo yum groupinstall "Development Tools"

Mac OS X

Installing prerequisites on Mac OS X:

xcode-select --install
sudo easy_install pip
sudo pip install virtualenv
brew install pkg-config libffi

OpenSUSE

Installing prerequisites on openSUSE:

sudo zypper in -t pattern devel_basis
sudo zypper in python-pip python-setuptools sqlite3 python-virtualenv \
               python-devel libffi-devel libopenssl-devel libjpeg62-devel

OpenBSD

Installing prerequisites on OpenBSD:

doas pkg_add python libffi py-pip py-setuptools sqlite3 py-virtualenv \
              libxslt jpeg

There is currently no port for OpenBSD. Additionally, OpenBSD's security settings require a slightly more difficult installation process.

XXX: I suspect this is out of date.

1. Create a new directory in /usr/local called _synapse. Also, create a new user called _synapse and set that directory as the new user's home. This is required because, by default, OpenBSD only allows binaries which need write and execute permissions on the same memory space to be run from /usr/local.
2. su to the new _synapse user and change to their home directory.
3. Create a new virtualenv: virtualenv -p python2.7 ~/.synapse
4. Source the virtualenv configuration located at /usr/local/_synapse/.synapse/bin/activate. This is done in ksh by using the . command, rather than bash's source.
5. Optionally, use pip to install lxml, which Synapse needs to parse webpages for their titles.
6. Use pip to install this repository: pip install matrix-synapse
7. Optionally, change _synapse's shell to /bin/false to reduce the chance of a compromised Synapse server being used to take over your box.

After this, you may proceed with the rest of the install directions.

Windows

If you wish to run or develop Synapse on Windows, the Windows Subsystem For Linux provides a Linux environment on Windows 10 which is capable of using the Debian, Fedora, or source installation methods. More information about WSL can be found at https://docs.microsoft.com/en-us/windows/wsl/install-win10 for Windows 10 and https://docs.microsoft.com/en-us/windows/wsl/install-on-server for Windows Server.

Troubleshooting Installation

XXX a bunch of this is no longer relevant.

Synapse requires pip 8 or later, so if your OS provides too old a version you may need to manually upgrade it::

sudo pip install --upgrade pip

Installing may fail with Could not find any downloads that satisfy the requirement pymacaroons-pynacl (from matrix-synapse==0.12.0). You can fix this by manually upgrading pip and virtualenv::

sudo pip install --upgrade virtualenv

You can next rerun virtualenv -p python3 synapse to update the virtual env.

Installing may fail during installing virtualenv with InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning. You can fix this by manually installing ndg-httpsclient::

pip install --upgrade ndg-httpsclient

Installing may fail with mock requires setuptools>=17.1. Aborting installation. You can fix this by upgrading setuptools::

pip install --upgrade setuptools

If pip crashes mid-installation for reason (e.g. lost terminal), pip may refuse to run until you remove the temporary installation directory it created. To reset the installation::

rm -rf /tmp/pip_install_matrix

pip seems to leak lots of memory during installation. For instance, a Linux host with 512MB of RAM may run out of memory whilst installing Twisted. If this happens, you will have to individually install the dependencies which are failing, e.g.::

pip install twisted

Prebuilt packages

As an alternative to installing from source, prebuilt packages are available for a number of platforms.

Docker images and Ansible playbooks

There is an offical synapse image available at https://hub.docker.com/r/matrixdotorg/synapse which can be used with the docker-compose file available at contrib/docker. Further information on this including configuration options is available in the README on hub.docker.com.

Alternatively, Andreas Peters (previously Silvio Fricke) has contributed a Dockerfile to automate a synapse server in a single Docker image, at https://hub.docker.com/r/avhost/docker-matrix/tags/

Slavi Pantaleev has created an Ansible playbook, which installs the offical Docker image of Matrix Synapse along with many other Matrix-related services (Postgres database, riot-web, coturn, mxisd, SSL support, etc.). For more details, see https://github.com/spantaleev/matrix-docker-ansible-deploy

Debian/Ubuntu

Matrix.org packages

Matrix.org provides Debian/Ubuntu packages of the latest stable version of Synapse via https://matrix.org/packages/debian/. To use them:

sudo apt install -y lsb-release curl apt-transport-https
echo "deb https://matrix.org/packages/debian `lsb_release -cs` main" |
    sudo tee /etc/apt/sources.list.d/matrix-org.list
curl "https://matrix.org/packages/debian/repo-key.asc" |
    sudo apt-key add -
sudo apt update
sudo apt install matrix-synapse-py3

Downstream Debian/Ubuntu packages

For buster and sid, Synapse is available in the Debian repositories and it should be possible to install it with simply:

    sudo apt install matrix-synapse

There is also a version of matrix-synapse in stretch-backports. Please see the Debian documentation on backports for information on how to use them.

We do not recommend using the packages in downstream Ubuntu at this time, as they are old and suffer from known security vulnerabilities.

Fedora

Synapse is in the Fedora repositories as matrix-synapse:

sudo dnf install matrix-synapse

Oleg Girko provides Fedora RPMs at https://obs.infoserver.lv/project/monitor/matrix-synapse

OpenSUSE

Synapse is in the OpenSUSE repositories as matrix-synapse:

sudo zypper install matrix-synapse

SUSE Linux Enterprise Server

Unofficial package are built for SLES 15 in the openSUSE:Backports:SLE-15 repository at https://download.opensuse.org/repositories/openSUSE:/Backports:/SLE-15/standard/

ArchLinux

The quickest way to get up and running with ArchLinux is probably with the community package https://www.archlinux.org/packages/community/any/matrix-synapse/, which should pull in most of the necessary dependencies.

pip may be outdated (6.0.7-1 and needs to be upgraded to 6.0.8-1 ):

sudo pip install --upgrade pip

If you encounter an error with lib bcrypt causing an Wrong ELF Class: ELFCLASS32 (x64 Systems), you may need to reinstall py-bcrypt to correctly compile it under the right architecture. (This should not be needed if installing under virtualenv):

sudo pip uninstall py-bcrypt
sudo pip install py-bcrypt

FreeBSD

Synapse can be installed via FreeBSD Ports or Packages contributed by Brendan Molloy from:

• Ports: cd /usr/ports/net-im/py-matrix-synapse && make install clean
• Packages: pkg install py27-matrix-synapse

NixOS

Robin Lambertz has packaged Synapse for NixOS at: https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/services/misc/matrix-synapse.nix

Setting up Synapse

Once you have installed synapse as above, you will need to configure it.

TLS certificates

The default configuration exposes two HTTP ports: 8008 and 8448. Port 8008 is configured without TLS; it should be behind a reverse proxy for TLS/SSL termination on port 443 which in turn should be used for clients. Port 8448 is configured to use TLS for Federation with a self-signed or verified certificate, but please be aware that a valid certificate will be required in Synapse v1.0.

If you would like to use your own certificates, you can do so by changing tls_certificate_path and tls_private_key_path in homeserver.yaml; alternatively, you can use a reverse-proxy. Apart from port 8448 using TLS, both ports are the same in the default configuration.

ACME setup

Synapse v1.0 will require valid TLS certificates for communication between servers (port 8448 by default) in addition to those that are client-facing (port 443). In the case that your server_name config variable is the same as the hostname that the client connects to, then the same certificate can be used between client and federation ports without issue. Synapse v0.99.0+ will provision server-to-server certificates automatically for you for free through Let's Encrypt if you tell it to.

In order for Synapse to complete the ACME challenge to provision a certificate, it needs access to port 80. Typically listening on port 80 is only granted to applications running as root. There are thus two solutions to this problem.

Using a reverse proxy

A reverse proxy such as Apache or nginx allows a single process (the web server) to listen on port 80 and proxy traffic to the appropriate program running on your server. It is the recommended method for setting up ACME as it allows you to use your existing webserver while also allowing Synapse to provision certificates as needed.

For nginx users, add the following line to your existing server block:

location /.well-known/acme-challenge {
    proxy_pass http://localhost:8009/;
}

For Apache, add the following to your existing webserver config::

ProxyPass /.well-known/acme-challenge http://localhost:8009/.well-known/acme-challenge

Make sure to restart/reload your webserver after making changes.

Authbind

authbind allows a program which does not run as root to bind to low-numbered ports in a controlled way. The setup is simpler, but requires a webserver not to already be running on port 80. This includes every time Synapse renews a certificate, which may be cumbersome if you usually run a web server on port 80. Nevertheless, if you're sure port 80 is not being used for any other purpose then all that is necessary is the following:

Install authbind. For example, on Debian/Ubuntu:

sudo apt-get install authbind

Allow authbind to bind port 80:

sudo touch /etc/authbind/byport/80
sudo chmod 777 /etc/authbind/byport/80

When Synapse is started, use the following syntax::

authbind --deep <synapse start command>

Finally, once Synapse is able to listen on port 80 for ACME challenge requests, it must be told to perform ACME provisioning by setting enabled to true under the acme section in homeserver.yaml:

acme:
    enabled: true

Registering a user

You will need at least one user on your server in order to use a Matrix client. Users can be registered either via a Matrix client, or via a commandline script.

To get started, it is easiest to use the command line to register new users. This can be done as follows:

$ source ~/synapse/env/bin/activate
$ synctl start # if not already running
$ register_new_matrix_user -c homeserver.yaml https://localhost:8448
New user localpart: erikj
Password:
Confirm password:
Make admin [no]:
Success!

This process uses a setting registration_shared_secret in homeserver.yaml, which is shared between Synapse itself and the register_new_matrix_user script. It doesn't matter what it is (a random value is generated by --generate-config), but it should be kept secret, as anyone with knowledge of it can register users on your server even if enable_registration is false.

Setting up a TURN server

For reliable VoIP calls to be routed via this homeserver, you MUST configure a TURN server. See docs/turn-howto.rst for details.

URL previews

Synapse includes support for previewing URLs, which is disabled by default. To turn it on you must enable the url_preview_enabled: True config parameter and explicitly specify the IP ranges that Synapse is not allowed to spider for previewing in the url_preview_ip_range_blacklist configuration parameter. This is critical from a security perspective to stop arbitrary Matrix users spidering 'internal' URLs on your network. At the very least we recommend that your loopback and RFC1918 IP addresses are blacklisted.

This also requires the optional lxml and netaddr python dependencies to be installed. This in turn requires the libxml2 library to be available - on Debian/Ubuntu this means apt-get install libxml2-dev, or equivalent for your OS.