How to block all but one or two websites without browser extensions?

Question

I want to block all, but one or two websites. This question is therefore relatively close to, but different from the following

• Parental controls with different settings for different users (difference: Parental control is not really a good flashship.)
• How to block websites temporarily? (difference: This is on how to block a particular website. I want to block everything except the ones I need.)

I know that this can be done with leechblock (for FF) or something similar for other browsers. I think that is not a very clean solution, because it is browser-based. I know this was both possible and easy with Firestarter but that package is deprecated.

I am looking for something which is both easy (not manually editing hosts, but a script for instance) and systemwide. It can use the CLI.

I would love a relatively detailed answer rather than just links to other websites - screenshots would be most welcome.

Answer 1

You can block websites system-wide by adding entry to hosts file. It works same as in windows.

Here's how to do it :

Open terminal and type :

sudo nano /etc/hosts

append the file with

127.0.0.1 facebook.com

Now whenever you'll visit facebook.com it will take you to localhost. FYI, it is not re-direct.

Worth reading: http://www.howtogeek.com/howto/27350/beginner-geek-how-to-edit-your-hosts-file/