There are two methods of doing this. One is to simply have the user kicked from the server so they are no longer using up one of your server slots and the other is to have them moved to a specific channel so that they are out of the way and everyone else knows that they are AFK. To setup AFK management on your server follow these simle steps below:
1) Open your Ventrilo client on your computer.
2) Connect to your Ventrilo server and be sure to login with admin privileges.
3) Right-click on a blank space within your Ventrilo client.
4) Navigate to “Server Admin” and then select “Server Properties”
5) Now take note of the options in the top right-hand corner of this screen labeled “User Inactivity”:
This is where you set how many minutes of inactivity before the server marks the user as AFK and also where you choose to have them moved to a channel or simply kicked from the server (kicking a player does not ban them in any form so they can simply reconnect if needed when they get back to their computer).
Change these settings to match your desires then click on the “Send”
button at the bottom of the page and you are done! It’s a simple as that.