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Forum Discussion

Techgeeeg_28888's avatar
Techgeeeg_28888
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Jan 03, 2013

DNS Query Flow

Hi Everyone,   I have a small query realted to DNS query and how GTM works.     I have GTM configured with 2 ISP links and acts as DNS. Now i need to know the following     1) A cl...
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Gregory_Thiell's avatar
Gregory_Thiell
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Aug 04, 2015

Techgeeeg,

 

Step number 2 you mentioned should not happen because by default, the TTL returned when you configure a Wide IP is set to 0. Therefore, the LDNS should not cache the entry. Instead, it should send a DNS request to your GTM for each client's request (which means, possibly multiple times for the same client, if the client also honors the TTL).

 

You can verify the TTL in ZoneRunner or by sending DNS requests with dig, for example.

 

Gregory_Thiell's avatar
Gregory_Thiell
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Aug 06, 2015
Edit: the default TTL is not 0 but 30s. So the record should be cached for 30s.