Rewriting RTSP uri

I have a RTSP Virtual Server setup and when a client attempts to connect using the virtual server IP the RTSP uri is passed to the backend server with the virtual server address (ie rtsp:///folder/resourece.rs).

 

 

I would like to rewrite this uri with the backend server's ip. I know that I can get the data by using the command

 

 

if {[string tolower [RTSP::uri]] contains "vip address" } {

 

 

but I am not sure how to only replace the vip address and leave the rest of the string intact. Any ideas?

 

 

The uri returns the following: rtsp:///folder/resourece.rs

 

 

Thanks!