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Forum Discussion

Macaron's avatar
Macaron
Icon for Nimbostratus rankNimbostratus
Aug 30, 2017

GTM resolving to wrong IP address from Internet

Hi Guys, I am in middle of an ongoing issue in which I am not able to resolve a DNS name of wide IP B to correct IP address. I have configured two new applications having the same VS on LTM (206.221....
application delivery
BIG-IP DNS
LTM
security
Macaron's avatar
Macaron
Icon for Nimbostratus rankNimbostratus
Aug 30, 2017

Hi eben, On GTM all ports are open for now. I have configured 0 for ports. But on LTM I am allowing 5 ports via an iRule.

 

Also, I did Wireshark capture on GTM listener IP to see the name resolution of wide IP B. I saw their GTM is actually replying with correct IP address (206.221.101.12) but answer in nslookup comes back as IP address of wide IP A (172.x.x.x). The NAT on ISP firewall changing this when GTM reply back to a query but it should not change since DNS is part of the payload and the NAT should have no bearing on this.

 

It is a bit confusing please, let me know which of my question you did not understand, I will try to explain again.

 

Thanks for your help.