Webpage redirect when system down

I am very new to Load Balancing. My only previous experience is with a CoyotePoint product

 

which was no where near as versatile as the F5 I have currently.

 

 

What I have set up.

 

3400LTM (9.3.1 Build 58) with a 2 node cluster web application.

 

 

Once a month I take it down to perform minor system maintenance and cold backups of data

 

While this is done there is no web based notification for users to see during the downtime.

 

 

What I need.

 

Is a way to send users to a web page that lets them know that the system is down.

 

 

 

Is this possible in the LTM?

 

 

When the LTM was set up by the F5 engineer we talked about this and I got the impression

 

that it was possible, but I may have misunderstood him.

 

 

Thanks for any help,

 

William