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Benoit_C_'s avatar
Benoit_C_
Jun 07, 2013

GTM private IP versus public IP in GTM DNS answers

Hello all,     I have a question regarding the behavior of the GTM in the following conditions:     GTM must reply to DNS queries only coming from Internet, ie with public IP address...
config
design
Hamish's avatar
Hamish
Icon for Cirrocumulus rankCirrocumulus
Jun 07, 2013
The translation address is NOT actually for the GTM to resolve addresses to. Confusing I know, it took me a while to get my head around that as the terminology is subject t some interpretation. It's actually the IP address the GTM will 'see' the remote VS as when/if it's NAT'ed between the GTM and the LTM. (Thus I never use it as my GTM's and LTM's are all within the private network).

 

 

If you wish to take the VS RFC private IP and have GTM resolve it instead as a translated address, you'll have to use an iRule.

 

 

BTW. Why have you defined the LTM as a generic LB? It's much better as a BigIP using BigIP monitoring. (The LTM then feeds the status and load of all the VS's back to the GTM via big3d daemon).

 

 

H