dendrite/docs/INSTALL.md

Installing Dendrite

Dendrite can be run in one of two configurations:

• Polylith mode: A cluster of individual components, dealing with different aspects of the Matrix protocol (see WIRING.md). Components communicate with each other using internal HTTP APIs and Apache Kafka. This will almost certainly be the preferred model for large-scale deployments.

• Monolith mode: All components run in the same process. In this mode, Kafka is completely optional and can instead be replaced with an in-process lightweight implementation called Naffka. This will usually be the preferred model for low-volume, low-user or experimental deployments.

For most deployments, it is recommended to run in monolith mode with PostgreSQL databases.

Regardless of whether you are running in polylith or monolith mode, each Dendrite component that requires storage has its own database. Both Postgres and SQLite are supported and can be mixed-and-matched across components as needed in the configuration file.

Be advised that Dendrite is still in development and it's not recommended for use in production environments just yet!

Requirements

Dendrite requires:

• Go 1.15 or higher
• Postgres 9.6 or higher (if using Postgres databases, not needed for SQLite)

If you want to run a polylith deployment, you also need:

• Apache Kafka 0.10.2+

Please note that Kafka is not required for a monolith deployment.

Building Dendrite

Start by cloning the code:

git clone https://github.com/matrix-org/dendrite
cd dendrite

Then build it:

./build.sh

Install Kafka (polylith only)

Install and start Kafka (c.f. scripts/install-local-kafka.sh):

KAFKA_URL=http://archive.apache.org/dist/kafka/2.1.0/kafka_2.11-2.1.0.tgz

# Only download the kafka if it isn't already downloaded.
test -f kafka.tgz || wget $KAFKA_URL -O kafka.tgz
# Unpack the kafka over the top of any existing installation
mkdir -p kafka && tar xzf kafka.tgz -C kafka --strip-components 1

# Start the zookeeper running in the background.
# By default the zookeeper listens on localhost:2181
kafka/bin/zookeeper-server-start.sh -daemon kafka/config/zookeeper.properties

# Start the kafka server running in the background.
# By default the kafka listens on localhost:9092
kafka/bin/kafka-server-start.sh -daemon kafka/config/server.properties

On macOS, you can use Homebrew for easier setup of Kafka:

brew install kafka
brew services start zookeeper
brew services start kafka

Configuration

PostgreSQL database setup

Assuming that PostgreSQL 9.6 (or later) is installed:

• Create role, choosing a new password when prompted:

  sudo -u postgres createuser -P dendrite
  

At this point you have a choice on whether to run all of the Dendrite components from a single database, or for each component to have its own database. For most deployments, running from a single database will be sufficient, although you may wish to separate them if you plan to split out the databases across multiple machines in the future.

On macOS, omit sudo -u postgres from the below commands.

• If you want to run all Dendrite components from a single database:

    sudo -u postgres createdb -O dendrite dendrite
  

  ... in which case your connection string will look like postgres://user:pass@database/dendrite.

• If you want to run each Dendrite component with its own database:

  for i in mediaapi syncapi roomserver signingkeyserver federationsender appservice keyserver userapi_accounts userapi_devices naffka; do
      sudo -u postgres createdb -O dendrite dendrite_$i
  done
  

  ... in which case your connection string will look like postgres://user:pass@database/dendrite_componentname.

SQLite database setup

WARNING: SQLite is suitable for small experimental deployments only and should not be used in production - use PostgreSQL instead for any user-facing federating installation!

Dendrite can use the built-in SQLite database engine for small setups. The SQLite databases do not need to be pre-built - Dendrite will create them automatically at startup.

Server key generation

Each Dendrite installation requires:

• A unique Matrix signing private key
• A valid and trusted TLS certificate and private key

To generate a Matrix signing private key:

./bin/generate-keys --private-key matrix_key.pem

WARNING: Make sure take a safe backup of this key! You will likely need it if you want to reinstall Dendrite, or any other Matrix homeserver, on the same domain name in the future. If you lose this key, you may have trouble joining federated rooms.

For testing, you can generate a self-signed certificate and key, although this will not work for public federation:

./bin/generate-keys --tls-cert server.crt --tls-key server.key

If you have server keys from an older Synapse instance, convert them to Dendrite's PEM format and configure them as old_private_keys in your config.

Configuration file

Create config file, based on dendrite-config.yaml. Call it dendrite.yaml. Things that will need editing include at least:

• The server_name entry to reflect the hostname of your Dendrite server
• The database lines with an updated connection string based on your desired setup, e.g. replacing database with the name of the database:
  • For Postgres: postgres://dendrite:password@localhost/database, e.g.
    • postgres://dendrite:password@localhost/dendrite_userapi_account to connect to PostgreSQL with SSL/TLS
    • postgres://dendrite:password@localhost/dendrite_userapi_account?sslmode=disable to connect to PostgreSQL without SSL/TLS
  • For SQLite on disk: file:component.db or file:///path/to/component.db, e.g. file:userapi_account.db
  • Postgres and SQLite can be mixed and matched on different components as desired.
• The use_naffka option if using Naffka in a monolith deployment

There are other options which may be useful so review them all. In particular, if you are trying to federate from your Dendrite instance into public rooms then configuring key_perspectives (like matrix.org in the sample) can help to improve reliability considerably by allowing your homeserver to fetch public keys for dead homeservers from somewhere else.

WARNING: Dendrite supports running all components from the same database in PostgreSQL mode, but this is NOT a supported configuration with SQLite. When using SQLite, all components MUST use their own database file.

Starting a monolith server

It is possible to use Naffka as an in-process replacement to Kafka when using the monolith server. To do this, set use_naffka: true in your dendrite.yaml configuration and uncomment the relevant Naffka line in the database section. Be sure to update the database username and password if needed.

The monolith server can be started as shown below. By default it listens for HTTP connections on port 8008, so you can configure your Matrix client to use http://servername:8008 as the server:

./bin/dendrite-monolith-server

If you set --tls-cert and --tls-key as shown below, it will also listen for HTTPS connections on port 8448:

./bin/dendrite-monolith-server --tls-cert=server.crt --tls-key=server.key

Starting a polylith deployment

The following contains scripts which will run all the required processes in order to point a Matrix client at Dendrite.

nginx (or other reverse proxy)

This is what your clients and federated hosts will talk to. It must forward requests onto the correct API server based on URL:

• /_matrix/client to the client API server
• /_matrix/federation to the federation API server
• /_matrix/key to the federation API server
• /_matrix/media to the media API server

See docs/nginx/polylith-sample.conf for a sample configuration.

Client API server

This is what implements CS API endpoints. Clients talk to this via the proxy in order to send messages, create and join rooms, etc.

./bin/dendrite-polylith-multi --config=dendrite.yaml clientapi

Sync server

This is what implements /sync requests. Clients talk to this via the proxy in order to receive messages.

./bin/dendrite-polylith-multi --config=dendrite.yaml syncapi

Media server

This implements /media requests. Clients talk to this via the proxy in order to upload and retrieve media.

./bin/dendrite-polylith-multi --config=dendrite.yaml mediaapi

Federation API server

This implements the federation API. Servers talk to this via the proxy in order to send transactions. This is only required if you want to support federation.

./bin/dendrite-polylith-multi --config=dendrite.yaml federationapi

Internal components

This refers to components that are not directly spoken to by clients. They are only contacted by other components. This includes the following components.

Room server

This is what implements the room DAG. Clients do not talk to this.

./bin/dendrite-polylith-multi --config=dendrite.yaml roomserver

Federation sender

This sends events from our users to other servers. This is only required if you want to support federation.

./bin/dendrite-polylith-multi --config=dendrite.yaml federationsender

Appservice server

This sends events from the network to application services running locally. This is only required if you want to support running application services on your homeserver.

./bin/dendrite-polylith-multi --config=dendrite.yaml appservice

Key server

This manages end-to-end encryption keys for users.

./bin/dendrite-polylith-multi --config=dendrite.yaml keyserver

Signing key server

This manages signing keys for servers.

./bin/dendrite-polylith-multi --config=dendrite.yaml signingkeyserver

EDU server

This manages processing EDUs such as typing, send-to-device events and presence. Clients do not talk to

./bin/dendrite-polylith-multi --config=dendrite.yaml eduserver

User server

This manages user accounts, device access tokens and user account data, amongst other things.

./bin/dendrite-polylith-multi --config=dendrite.yaml userapi