GTM iRule Needed for DNS persistence

I need an iRule that enables LDNS persistence for LDNS servers with a SRC IP of 67.X.X.X and 78.X.X.X. In addition to enabling persistence, it must mirror the persistence within those IP ranges (i.e., anything persistant to 78.X must also be persistent to 67.X).

 

 

I also need the DNS response to failover correctly if I have an outage to the pool.

 

 

Use-Case:

 

I have an application that requires DNS persistence. I have static persist enabled and a /16 CIDR IPv4 mask configured on the GTM. However, some users have DNS servers configured that bounce between IPs (using DNS farms). THus, my GTM sees the LDNS bouncing between multiple SRC IPs and thus, the GTM gives out multiple DNS responses. THis breaks the application.

 

 

Thanks in Advance, Andrew