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Forum Discussion

MarcelNL_153054's avatar
MarcelNL_153054
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May 06, 2014

GTM placement for public DNS

Hi, I got my hands on a GTM with version 9.4.5, which I want to use as a public DNS for jy domains. I have also bought a LTM which I will use as a reverse proxy for my webservers. What i cannot f...
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Cory_50405's avatar
Cory_50405
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May 07, 2014

The GTM can really be placed anywhere, as long as it can be reached by external users for DNS queries. It is only going to handle the DNS traffic. Any subsequent data connection (HTTP, FTP, etc.) is going to go directly to the LTM. So essentially there are two separate communication flows:

 

DNS (UDP or TCP port 53):

 

External client queries for one of your domains (www.company.com for example). The query will traverse through the normal DNS root servers and ultimately arrive at your GTM. Your GTM will provide a response based on a configured wide IP, ZoneRunner record, etc. This response will be for a virtual server IP address hosted on your LTM.

 

Data (TCP port 80 in this case):

 

After the client has resolved the FQDN, it'll then attempt its data connection. Let's say it's a web connection. The client will begin an HTTP connection to the LTM virtual server IP address that it was given when it performed the DNS lookup.