Admin Announcements/Restart Messages

[Petroph]

Is there a way to announce messages to everyone on the server that is NOT in the chat box? There are times where people are talking to fast, and messages are gone before they are read. So

1. How to make announcement messages for the whole server?
2. How to restart server with a set time limit, with countdown messages?

 

[Zaflis]

/shutdown 120
will turn off in 2 minutes, and display countdown timer for everyone.