BIG-IP DNS monitors internal ip and gives dns answers on a dummy ip

Guys,

I guess this is a very old question which I am asking in the forum, but I am trying to get my head around hoping for some help/advice.

My BIG-DNS is up and working fine dishing out external ips for dns records which is all good.Some of the VS are configured on LTMs and some of them are standalone servers attached to Web FE DMZ of a firewall which are natted to internal ip address.

BIG-IP DNS monitors the external ip of the VS on the LTM as well as on the firewall. This is how I have done to monitor the servers on firewall : BIP-IP DNS (private ip) ----> natted to public ip ------> this public ip of big-ip dns then monitors the external natted ip of the server on the FE firewall.

Now I am in situation where I want to dish out 128.128.128.100 for a url which is being natted to internal ip address lets say 192.168.100.10 , so my question is how can i achieve this as 128.128.128.100 is dummy ip and in this case my BIG-IP dns which has a genuine public ip can't see this dummy ip.

I know people have posted some solutions based on irules, but as I am quiet reluctant to use irules on dns as my system is in production from quiet a sometime and I don't want to break anything.

Is there any simple solution to this.

On a side note, cisco gss can monitor the internal ip address and dish out the external 128.128.128.100 ip for the url but the same thing is proving to be difficult on F5.

Thanks, Pan

So many genius minds out there, anyone who can provide some help.

If it is not possible without irules, then please show me the irule way and I will try to implement it.

Many Thanks, Pan

Have you read this article K14707: Configuring BIG-IP DNS server objects for BIG-IP devices that reside behind a firewall NAT?