dcomms

Decentralized communications that work with or without the Internet

Prerequisites

• docker using the docker guide (https://docs.docker.com/engine/install/)
• curl, aria2, tor
• A directory named /var/www/dcomms created on the host for the website document root.
• A subdomain with the A record pointed to the IP address of a node for automatic issuance of a Let's Encrypt SSL certificate.
• A subdomain with the MX record pointed to the A record of a node for DeltaChat mail delivery.
• (Optional) A Tor hidden service configured, and listening on port 80 and 8448.

Hardware requirements

The system requirements will depend on several factors, including user-count, federation level, services and selecte, so we recommend choosing a system configuration that allows for the addition of resources.
A bare minimum system running all services for a small number of users would require:

• 4GB RAM
• 2 Cores
• 50Gb disk

Whereas a deployment running all services for hundres of users would require:

• 16GB RAM
• 4 Cores
• 200Gb disk

The previous configuration could potentially scale to a user count of near 1000, if the level of user activity is low, however if each service is very active and federated then we recommend a minimum of:

• 32GB RAM
• 16 Cores
• 1TB disk

Introduction

dcomms is a bundle of decentralized communication software running as services in the form of a docker swarm stack.

It is used to rapidly deploy a server hosting a variety of decentralized, encrypted, and federated communications platforms such as Matrix and DeltaChat across multiple hosts.

Let's Encrypt TLS certificates are automatically issued and managed by the Caddy container across all services.

Service containers

The dcomms stack leverages single node, non-replicated containers of the following services built from the latest images below:

• CENO client courtesy of censorship.no
• Synapse Docker courtesy of matrix.org
• Element courtesy of vector-im
• Mau courtesy of the maubot dev team
• Caddy courtesy of the Caddy Docker Maintainers
• docker-mailadm, includes dovecot and postfix, courtesy of DeltaChat
• Mastodon, a modified version of the original Mastodon container that includes sendmail.

Ports

CENO: client: 28729/udp
Caddy: (webserver): 443/tcp, 80/tcp, 8448/tcp
DeltaChat: (postfix/dovecot): 587/tcp 143/tcp
Synapse: 8448/tcp
Peertube: 1935/tcp 1936/tcp (if livestreaming enabled)

• Note: dcomms leverages docker host networking and therefore we recommend denying access to all other unnecessary ports at the host level.

Installation

Point the following A records to the docker worker you wish to use for deployment:

matrix.server1.example.org -> IP of your server
chat.server1.example.org -> IP of your server
peertube.server1.example.org -> IP of your server
server1.example.org -> IP of your server

Point the following MX record to the A record:

server1.example.org -> server1.example.org

Clone or download this repository. Review ./install.sh and make any that may be required for your environment.

Install

Once your server meets the prerequisites, installation simply involves running ./install.sh and responding to any prompts. Configs will be automatically placed in your DCOMMS_DIR and a run.sh script will be generated.

• Note: If you wish to reinstall dcomms you will need to delete all docker volumes, and the conf directory in DCOMMS_DIR before running install.sh again.

Redeploy

In the future, if you need to start the dcomms containers again simply run the ./run.sh program in your DCOMMS_DIR.

Tor

If you wish to provide users with a Tor hidden service address by which they can access your services, you must first install and configure Tor. The script will detect if you have Tor installed and prompt you for a hidden service address. You can find this in the hostname file in your HiddenServiceDir.

Example:

cat /var/lib/tor/onion_service/hostname

Post installation

• Copy a pre-existing website into /var/www/dcomms/ across all docker nodes or checkout all files from either the dcomms-web repo (UA) or the chatv3 repo (RU) into the same location.
• Optionally visit https://server1.example.org to view the website.
• Optionally visit https://chat.server1.example.org to view the Element service.
• Optionally configure a Matrix client to use https://matrix.server1.example.org as the homeserver.

Troubleshooting

Log review

Altering configs

Specific issues with services