Mattermost is both the name of the company and the software solution it offers. It provides a Slack-like chat tool specifically designed for team communication. It offers a free, open-source version and two enterprise editions with advanced features. As an alternative to proprietary SaaS messaging, Mattermost consolidates all team communication in one place, making it searchable and accessible from anywhere. It’s built with Golang and React and runs as a production-ready Linux binary under the MIT license, using MySQL or Postgres. In this article, we will show you how to install Mattermost on Ubuntu 26.04.
Table of Contents
Prerequisites
- An Ubuntu 26.04 VPS with at least 2GB of RAM
- SSH access with sudo privileges, or root access.
Conventions
# – given commands should be executed with root privileges either directly as a root user or by use of sudo command
$ – given commands should be executed as a regular userStep 1. Log in to your server via SSH
First of all, let us log in to our Ubuntu 26.04 VPS via SSH as the root user:
ssh root@IP_Address -p Port_numberYou will need to replace ‘IP_Address’ and ‘Port_number’ with your server’s respective IP address and SSH port number. Additionally, replace ‘root’ with the username of the system user with sudo privileges.
Now, let’s check whether you have the proper Ubuntu version installed on your server with the following command:
$ lsb_release -aThe command should return an output like this:
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 26.04 LTS
Release: 26.04
Codename: resoluteIn this article, we run the commands as root and as the Mattermost user. Please pay attention to the symbol shown before the commands.
Step 2. Update the system
Before starting, we need to ensure that all Ubuntu 26.04 packages installed on the server are up to date. You can do this by running the following commands:
# apt updateThe list of available packages in the system package index has now been refreshed. Let’s proceed to the next step.
Step 3. Create a System User
In this step, we will create a new system user called “mattermost”. Let’s execute the command below; you can substitute ‘mattermost’ with any username you like.
# useradd -G sudo,www-data -s /bin/bash -m -d /opt/mattermost mattermostThat’s it; we have just created a new user called mattermost
Step 4. Install PostgreSQL Server
Initially, Mattermost supported MySQL and PostgreSQL. But, starting with Mattermost v11, support for MySQL has been completely removed from the codebase. So, PostgreSQL is the only supported database driver now. Let’s install the PostgreSQL server.
# apt install postgresql postgresql-contribOnce the installation is complete, PostgreSQL will automatically start and be up and running. It is also configured to automatically run upon a server reboot.
Step 5. Create a Database
We’re getting close to being able to install Mattermost on Ubuntu 26.04. Next, let’s create a PostgreSQL database. First, we need to log in as user ‘postgres’ then go to the PostgreSQL shell
# sudo -u postgres psqlOnce logged in, let’s run the commands below to create a database and user, and grant the user access.
CREATE DATABASE mattermost;
CREATE USER mattermost WITH PASSWORD 'm0d1fyth15';
GRANT ALL ON DATABASE mattermost TO mattermost;
ALTER DATABASE mattermost OWNER TO mattermost;
GRANT USAGE, CREATE ON SCHEMA PUBLIC TO mattermost;Next, we can verify the new PostgreSQL user; simply execute the \du command:
postgres=# \du
List of roles
Role name | Attributes
------------+------------------------------------------------------------
mattermost |
postgres | Superuser, Create role, Create DB, Replication, Bypass RLSNext, we can check the connection information.
# sudo -u postgres psql --host=localhost --dbname=mattermost --username=mattermost --passwordThe command above will prompt you for the Mattermost PostgreSQL user password. We created the user in the previous step.
After logging in to the PostgreSQL shell, you can run this command:
\conninfoOnce executed, the command will print this output:
psql (18.3 (Ubuntu 18.3-1))
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, compression: off, ALPN: postgresql)
Type "help" for help.
mattermost=> \conninfo
Connection Information
Parameter | Value
----------------------+------------------------
Database | mattermost
Client User | mattermost
Host | localhost
Host Address | 127.0.0.1
Server Port | 5432
Options |
Protocol Version | 3.0
Password Used | true
GSSAPI Authenticated | false
Backend PID | 27626
SSL Connection | true
SSL Library | OpenSSL
SSL Protocol | TLSv1.3
SSL Key Bits | 256
SSL Cipher | TLS_AES_256_GCM_SHA384
SSL Compression | false
ALPN | postgresql
Superuser | off
Hot Standby | off
(19 rows)
mattermost=> That’s it, a new database has been created. Let’s exit from the postgres user.
\q
$ exitStep 6. Download and Install Mattermost on Ubuntu 26.04
Let’s switch to the ‘mattermost’ user we created earlier, then download the installation files.
# su - mattermostGet the download link from their download page, then download it.
$ wget https://releases.mattermost.com/11.6.1/mattermost-11.6.1-linux-amd64.tar.gz -O mattermost.tar.gzThe installation file has been downloaded and saved as mattermost.tar.gz. Let’s extract the file right under the ‘mattermost’ user home directory.
$ tar -xzvf mattermost.tar.gz --strip-component 1Before running Mattermost, we need to configure it to connect to our database.
$ cp -a /opt/mattermost/config/config.json{,.orig}The command above saves a copy of config.json as config.json.orig. Now, let’s edit the config.json file to connect to the PostgreSQL database.
$ nano /opt/mattermost/config/config.jsonConfigure the following properties in this file:
"DataSource": "postgres://mmuser:mostest@localhost/mattermost_test?sslmode=disable\u0026connect_timeout=10\u0026binary_parameters=yes",Replace the lines with these:
"DataSource": "postgres://mattermost:m0d1fyth15@localhost/mattermost?sslmode=disable\u0026connect_timeout=10\u0026binary_parameters=yes",Make sure to use the correct database user and password you created earlier.
Set your “SiteURL”: Your domain name for the Mattermost server (e.g., https://mattermost.yourdomain.com).
Save the file, then exit from nano editor. We can exit from user ‘mattermost’ now.
$ exitStep 7. Create Systemd Service File
Before we install Mattermost on Ubuntu 26.04, we will manage the Mattermost service using systemd. Let’s create a systemd service file for Mattermost now.
# nano /etc/systemd/system/mattermost.servicePaste the following into the systemd service file, then save it.
[Unit]
Description=Mattermost
After=network.target
[Service]
Type=notify
ExecStart=/opt/mattermost/bin/mattermost
TimeoutStartSec=3600
KillMode=mixed
Restart=always
RestartSec=10
WorkingDirectory=/opt/mattermost
User=mattermost
Group=mattermost
LimitNOFILE=49152
[Install]
WantedBy=multi-user.targetSave the file, exit, and then reload systemd to refresh and apply the changes we made.
# systemctl daemon-reloadLet’s run Mattermost now and configure it to start automatically on server reboot.
# systemctl enable --now mattermostYour Mattermost service should be up and running now. To verify, run this command:
# systemctl status mattermostNow, you will see an output similar to this
● mattermost.service - Mattermost
Loaded: loaded (/etc/systemd/system/mattermost.service; enabled; preset: enabled)
Active: active (running) since Sat 2026-05-09 07:05:10 UTC; 1s ago
Invocation: 1832a281abf54cacbae2010ca3b528c0
Main PID: 32851 (mattermost)
Tasks: 37 (limit: 1605)
Memory: 366.3M (peak: 583M)
CPU: 13.028s
CGroup: /system.slice/mattermost.service
├─32851 /opt/mattermost/bin/mattermost
├─33098 plugins/mattermost-ai/server/dist/plugin-linux-amd64
├─33108 plugins/playbooks/server/dist/plugin-linux-amd64
└─33121 plugins/com.mattermost.calls/server/dist/plugin-linux-amd64
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.264 Z","level":"info","msg":"got public IP address for local interface","caller":"app/plugin_api.go:1139","plugin_id":"com.mattermost.calls","origin">
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.265 Z","level":"info","msg":"rtc: server is listening on udp 127.0.0.1:8443","caller":"app/plugin_api.go:1139","plugin_id":"com.mattermost.calls","or>
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.266 Z","level":"info","msg":"rtc: server is listening on udp 192.168.93.138:8443","caller":"app/plugin_api.go:1139","plugin_id":"com.mattermost.calls>
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.267 Z","level":"info","msg":"rtc: server is listening on udp 172.17.0.1:8443","caller":"app/plugin_api.go:1139","plugin_id":"com.mattermost.calls","o>
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.269 Z","level":"info","msg":"rtc: server is listening on udp 172.18.0.1:8443","caller":"app/plugin_api.go:1139","plugin_id":"com.mattermost.calls","o>
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.270 Z","level":"info","msg":"Listening TCP on 0.0.0.0:8443","caller":"app/plugin_api.go:1139","plugin_id":"com.mattermost.calls","origin":"main.(*log>
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.295 Z","level":"info","msg":"Starting Server...","caller":"app/server.go:872"}
May 09 07:05:10 ubuntu26 mattermost[32851]: {"timestamp":"2026-05-09 07:05:10.296 Z","level":"info","msg":"Server is listening on [::]:8065","caller":"app/server.go:948","address":"[::]:8065"}
May 09 07:05:10 ubuntu26 systemd[1]: Started mattermost.service - Mattermost.You should be able to access Mattermost at http://YOUR_SERVER_IP_ADDRESS:8065
Next up, you can click on the ‘View in Browser’ button to create a new account.
Step 8. Install and Configure Nginx
Mattermost is accessible at http://YOUR_SERVER_IP_ADDRESS:8065. To access Mattermost via a domain or subdomain without the port number at the end of the URL, we need to install and configure a reverse proxy. Let’s install and configure nginx.
# apt install nginx -yOnce installed, we can create an nginx server block for our Mattermost website.
# nano /etc/nginx/conf.d/mattermost.confThen, insert the following into the file.
upstream mm {
server 127.0.0.1:8065;
}
server {
listen 80;
server_name mattermost.yourdomain.com;
location ~ /api/v[0-9]+/(users/)?websocket$ {
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
client_max_body_size 50M;
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Frame-Options SAMEORIGIN;
proxy_buffers 256 16k;
proxy_buffer_size 16k;
client_body_timeout 60;
send_timeout 300;
lingering_timeout 5;
proxy_connect_timeout 90;
proxy_send_timeout 300;
proxy_read_timeout 90s;
proxy_http_version 1.1;
proxy_pass http://mm;
}
location / {
client_max_body_size 50M;
proxy_set_header X-Frame-Options SAMEORIGIN;
proxy_buffers 256 16k;
proxy_buffer_size 16k;
proxy_read_timeout 600s;
proxy_cache_revalidate on;
proxy_cache_min_uses 2;
proxy_cache_use_stale timeout;
proxy_cache_lock on;
proxy_http_version 1.1;
proxy_pass http://mm;
}
}Save the file, then exit from the editor and restart nginx
# systemctl restart nginxBringing It All Together
That’s it, you should be able to access Mattermost at http://mattermost.yourdomain.com now. You can use this address to connect using your mobile application or web browser.
Congratulations! You followed this article and have successfully installed Mattermost on your Ubuntu 26.04 server.
Of course, you don’t have to spend your time following this article to install Mattermost on your Ubuntu 26.04 server if you have an active Mattermost server with us, in which case you can simply ask our expert Linux admins to install Mattermost for you. Simply log in to the client area, then submit a ticket. Our expert administrators are available 24×7 and will respond to your request immediately. They will also help you install an SSL certificate on your Mattermost service.
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