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svs
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Sep 26, 2018

BIG-IP use of "Network > DNS Resolver"

Hi guys,

 

I was searching for a longer time now to find a useful description of the DNS resolver feature in the BIG-IP (no, I'm not talking about DNS a.k.a. GTM). The feature can be found in "Network > DNS Resolver". The configuration is pretty straight-forward, but unfortunately it seems that there is no documentation for this feature. I wasn't able to find anything useful. The only article on DevCentral, talking about this functionality was in https://devcentral.f5.com/questions/how-does-network-gt-gt-dns-resolver-work-47805, but the description is not really satisfying.

 

My questions are: * What is the feature used for? (I know, that there are some modules, that rely on configured DNS resolver) * Why do we need this? * Is there a list of modules, which already use the DNS resolver feature instead of DNS system configuration? * Is there any documentation, not talking about DNS module, related to DNS resolver?

 

I appreciate any answers or discussions.

 

Best regards, svs

 

  • A DNS Resolver (from the network settings) is used to resolve DNS names from TMM - such as an iRule resolving an IP address or an HTTP forward proxy profile.

     

    DNS configuration found within the system is for the Linux/Management part of the device.

     

  • A DNS resolver is an object that let you configure which DNS servers will be used.

     

    F5 seems to use it for new features like forward proxy, OCSP stappling, Proactive Bot Defense, AFM FQDN objects, ...

     

    All features existing before version 11.0 are still using system DNS configuration...