How to install Discourse Forum using Docker on CentOS 8

How to install Discourse Forum using Docker on CentOS 8

Discourse is a free and open source platform built for the next decade of the Internet. It is a modern forum software that can be used as a mailing list, discussion forum, long chat room, etc. It uses Ruby on Rails as the backend, Ember.js as the frontend, PostgreSQL as the data storage, and Redis as the cache server. It is simple, efficient, suitable for mobile devices, customizable, and makes online discussions easy and fun.

In this tutorial, we will show you how to install Discourse forum using Docker on CentOS 8 server.


  • Server running CentOS 8.
  • A valid domain name pointing to the server IP.
  • The root password is configured for the server.

Install Docker

First, you need to install Docker in the server. By default, Docker is not available in the CentOS 8 standard repository. Therefore, you need to add the official Docker repository to your system. You can add it with the following command:

dnf config-manager --add-repo=

After creating the repository, install Docker by running the following command:

dnf install docker-ce --nobest

After installing Docker, start the Docker service and use the following command to start it when the system restarts:

systemctl start dockersystemctl enable docker

You can now verify the Docker version with the following command:

docker --version

You should see the following output:

Docker version 20.10.1, build 831ebea

Install discourse

First, create a directory for Discourse using the following command:

mkdir /opt/discourse

Next, download the latest version of Discourse from the Git repository using the following command:

git clone /opt/discourse

Next, change the directory to Discourse and install Discourse using the following command:

cd /opt/discourse./discourse-setup

You will be asked to provide your FQDN as shown below:

which: no in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin)
which: no in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin)
Ports 80 and 443 are free for use
'samples/standalone.yml' -> 'containers/app.yml'
Found 4GB of memory and 2 physical CPU cores
setting db_shared_buffers = 1024MB
containers/app.yml memory parameters updated.

Hostname for your Discourse? []:

Provide your valid domain name and press Enter. You will be asked to provide a valid email address and password:

Checking your domain name . . .
Connection to succeeded.
Email address for admin account(s)? [[email protected],[email protected]]: [email protected]
SMTP server address? []:
SMTP port? [587]: 
SMTP user name? [[email protected]]: [email protected]
SMTP password? [pa$$word]: yourpassword
Optional email address for Let's Encrypt warnings? (ENTER to skip) [[email protected]]: [email protected]

Does this look right?

Provide all the details and press Enter. You will need to verify all settings as follows:

Hostname      :
Email         : [email protected]
SMTP address  :
SMTP port     : 587
SMTP username : [email protected]
SMTP password : yourpassword
Let's Encrypt : [email protected]

ENTER to continue, 'n' to try again, Ctrl+C to exit: 

If everything is normal, press Enter to start the installation. After the installation is complete, you will get the following output:

+ /usr/bin/docker run --shm-size=512m -d --restart=always -e LANG=en_US.UTF-8 -e RAILS_ENV=production -e UNICORN_WORKERS=4 -e UNICORN_SIDEKIQS=1 -e RUBY_GLOBAL_METHOD_CACHE_SIZE=131072 -e RUBY_GC_HEAP_GROWTH_MAX_SLOTS=40000 -e RUBY_GC_HEAP_INIT_SLOTS=400000 -e RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR=1.5 -e DISCOURSE_DB_SOCKET=/var/run/postgresql -e DISCOURSE_DB_HOST= -e DISCOURSE_DB_PORT= -e LETSENCRYPT_DIR=/shared/letsencrypt -e -e [email protected] -e -e DISCOURSE_SMTP_PORT=587 -e [email protected] -e DISCOURSE_SMTP_PASSWORD=yourpassword -e [email protected] -h centos8-app -e DOCKER_HOST_IP= --name app -t -p 80:80 -p 443:443 -v /var/discourse/shared/standalone:/shared -v /var/discourse/shared/standalone/log/var-log:/var/log --mac-address 02:e0:37:60:d3:09 local_discourse/app /sbin/boot

Now, you can use the following command to verify that Discourse runs the container:

docker ps

You should see the following output:

CONTAINER ID   IMAGE                 COMMAND        CREATED          STATUS          PORTS                                      NAMES
ab3bdf3c169d   local_discourse/app   "/sbin/boot"   22 seconds ago   Up 21 seconds>80/tcp,>443/tcp   app

Access Discourse Web UI

Now, open your web browser and enter the URL You will be redirected to the “Talk Settings” screen:

Click on register Button. You should see the “Registration” page:

Register an administrator accountadvertising

Provide your email, username, password, and click register Button. You should receive an email to activate your account.

confirm the email

in conclusion

Congratulations! You have successfully installed the Discourse forum software on CentOS 8. Now you can browse Discourse to get more features and deploy it in a production environment. If you have any questions, please feel free to ask me.