GitLab is an open-source alternative to the Microsoft-owned GitHub, and I wanted to give it a try. I am not sure I understand what it means to self-host GitLab: Does it mean that my Ubuntu PC transforms into a Server that has to be on for 24 hours?
Thank you.
The self-managed option gives you more control, but you need to deal with two things:
Hosting either on your own server in your own network or on a dedicated / virtual server leased from hosting providers on the Internet.
Installation and administration of the software itself.
The other option is (SaaS) which means gitlab.com takes care of the above for you.
More information here and here.
OS and hardware requirements are listed here.
Installation instructions are available here.
Notice:
A server does not need to run 24 hours, but the software / solutions on the server are only available when the server is up and running.
A server does not mean necessarily that Ubuntu server edition OS must be used. You can use Ubuntu desktop edition on a machine and use it like a server.
So basically you can install the self-managed Gitlab on your PC and turn the PC off when you are not using it if that is what you are asking.