irule & advanced routing module

Have been looking into advanced routing modules.

 

Would like to change cost of a route (or only send the route) for a vip address based on what nodes is up i.e.

 

if node a is up and b is down send route as normal

 

if node a is down and b is up make route higher cost (or do not send route)

 

 

From what I read, Route health injection is based on if vip is up so not exactly what I require.

 

 

I know I can check node status with irule. Can I influence advanced routing module with irule?

 

A link to an example irule and routing would be great.

 

 

thanks

 

Peter