#003 How to run SQL server on ubuntu; how to (re)start SQL server on ubuntu; how to stop SQL server on ubuntu

1 Install it first: https://docs.microsoft.com/en-us/sql/linux/quickstart-install-connect-ubuntu?view=sql-server-2017

2 Check:

~$ sudo systemctl status mssql-server

3 Do what you need:

~$ sudo systemctl stop mssql-server
~$ sudo systemctl start mssql-server
~$ sudo systemctl restart mssql-server