Introduction

Mattermost is an open-source platform for team communication. This guide will walk you through installing Mattermost with Nginx as a reverse proxy and securing it with a free SSL certificate from Let’s Encrypt on Ubuntu 24.04.

Prerequisites

• A server running Ubuntu 24.04
• Root access or a user with sudo privileges
• Domain name pointing to your server’s IP address

Step 1: Update the System

Start by updating your package list and upgrading your installed packages:

sudo apt update
sudo apt upgrade -y

Step 2: Install Required Dependencies

Install dependencies required for Mattermost and Nginx:

sudo apt install -y nginx postgresql postgresql-contrib

Step 3: Install Mattermost

Download the latest Mattermost server from the official website:

wget https://releases.mattermost.com/$(wget -qO- https://api.github.com/repos/mattermost/mattermost-server/releases/latest | grep tag_name | cut -d '"' -f 2)/mattermost-server-*.tar.gz

Extract Mattermost:

tar -xvzf mattermost-server-*.tar.gz

Move the Mattermost folder to the appropriate location:

sudo mv mattermost /opt/

Step 4: Configure PostgreSQL Database

Log into PostgreSQL and create a new database and user for Mattermost:

sudo -u postgres psql

Run the following commands in the PostgreSQL shell:

CREATE DATABASE mattermost_db;
CREATE USER mattermost_user WITH PASSWORD 'your_password';
GRANT ALL PRIVILEGES ON DATABASE mattermost_db TO mattermost_user;
\q

Step 5: Configure Mattermost

Edit the Mattermost configuration file:

sudo nano /opt/mattermost/config/config.json

Update the following settings:

"DriverName": "postgres",
"DataSource": "mattermost_user:your_password@tcp(localhost:5432)/mattermost_db?sslmode=disable",

Also set the SiteURL to your domain:

"SiteURL": "https://your_domain.com",

Step 6: Start Mattermost

Start the Mattermost server:

cd /opt/mattermost/bin
sudo ./mattermost 

To run Mattermost in the background, you can use screen or set it up with a service file.

Step 7: Install Nginx

Start Nginx and enable it to run on boot:

sudo systemctl start nginx
sudo systemctl enable nginx

Step 8: Configure Nginx as a Reverse Proxy

Create a new Nginx configuration file for Mattermost:

sudo nano /etc/nginx/sites-available/mattermost

Enter the following configuration:

server {
    listen 80;
    server_name your_domain.com;

    location / {
        proxy_pass http://localhost:8065;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;
    }
}

Enable the configuration:

sudo ln -s /etc/nginx/sites-available/mattermost /etc/nginx/sites-enabled/

Test the Nginx configuration:

sudo nginx -t

Restart Nginx:

sudo systemctl restart nginx

Step 9: Install Certbot for Let’s Encrypt SSL

Install Certbot:

sudo apt install certbot python3-certbot-nginx

Step 10: Obtain a Free SSL Certificate

Run Certbot to get your SSL certificate:

sudo certbot --nginx -d your_domain.com

Follow the instructions to complete the SSL setup. Certbot will automatically configure Nginx to use the new certificate.

Step 11: Test HTTPS Access

Open your browser and navigate to https://your_domain.com to verify that Mattermost is accessible over HTTPS.

Conclusion

You have successfully installed Mattermost with Nginx as a reverse proxy and secured it with a Let’s Encrypt SSL certificate on Ubuntu 24.04.

Resources

• Mattermost Official Website
• Mattermost Documentation
• Let’s Encrypt Official Website
• Nginx Official Website