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gtownbb_34308's avatar
gtownbb_34308
Icon for Nimbostratus rankNimbostratus
Mar 11, 2009

Issue setting up dns proxy on LTM

I am having an issue setting up DNS proxy on an LTM. I have added my DNS server to the BIND Forwarder Server List and have started named as well. When I point one of my servers dns requests to the floating IP on the F5 i get the following response back:

 

 

nslookup www.whatever.com x.x.x.x (floating ip on the f5)

 

Server: x.x.x.x

 

Address: x.x.x.x53

 

 

Non-authoritative answer:

 

*** Can't find www.whatever.com: No answer

 

 

If I ssh into the f5 and try and resolve the same name to the same dns server I get a successful response as follows:

 

 

www.whatever.com canonical name = whatever.com.

 

Name: whatever.com

 

Address: x.x.x.x

 

 

 

Any thoughts?

 

 

Thanks,

 

Bob
config
design

2 Replies

  • The_Bhattman's avatar
    The_Bhattman
    Icon for Nimbostratus rankNimbostratus
    Aug 05, 2009
    Hi Bob,

     

    Have you looked into the self address of the BIGIP to make sure port lockdown is either set to Allow Default or open for UDP 53?

     

     

    Hope this helps

     

    CB

     

     

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Feb 25, 2010
    I ran into this and found the fix is described in SOL5299:

     

     

    SOL5299: The BIG-IP system does not forward DNS requests after configuring the BIND Forwarder Server List

     

    https://support.f5.com/kb/en-us/solutions/public/5000/200/sol5299.html

     

     

    Aaron