For other system requirements, see System requirements for SQL Server on Linux.
1. Import the public repository GPG keys:
curl https://packages.microsoft.com/keys/microsoft.asc | sudo apt-key add -
2. Register the Microsoft SQL Server Ubuntu repository:
sudo add-apt-repository "$(curl https://packages.microsoft.com/config/ubuntu/16.04/mssql-server-2017.list)"
3. Run the following commands to install SQL Server:
sudo apt-get update
sudo apt-get install -y mssql-server
4. After the package installation finishes, run mssql-conf setup and follow the prompts to set the SA password and choose your edition.
sudo /opt/mssql/bin/mssql-conf setup
5. Once the configuration is done, verify that the service is running:
systemctl status mssql-server
6. If you plan to connect remotely, you might also need to open the SQL Server TCP port (default 1433) on your firewall.
Link to official website MS .NET:
https://docs.microsoft.com/en-us/sql/linux/quickstart-install-connect-ubuntu