Hi everyone 
Is there an easy/quick way to shut down the forum or stop posting for a certain period of time? Other than changing all categories settings.
Any help would be much appreciated!
Well, the easiest way is to setup your forum in read-only mode. This means that the site remains online and users can only read topics but can not interact (reply, open new topics, put Like etc).
Thanks Daniela can you tell me how to do that?
Nevermind! looked it up and found out.
Go to your https://your-site/admin/backups page and click the Enable read-only mode
You can also configure a global alert that tells users that the site is paused, so they stay quiet 
但是（我刚刚在 meta 上搜索类似帖子时了解到），必须用醒目的大字警告：一旦启用“只读”模式，在实验或进行操作期间，如果您不小心关闭了（无痕）浏览器标签页，或因任何原因退出登录，哪怕只有一分钟，您将无法重新登录！！
是的，可以通过 Rails 控制台实现：
Discourse.disable_readonly_mode(Discourse::USER_READONLY_MODE_KEY)