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Forum Discussion

Ispone_netadmin's avatar
Ispone_netadmin
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Feb 24, 2014

Need to allow only a few networks/IP blocks for DNS request

Hi,   We are trying to refine how our DNS LB is configured in F5. We are currently load balancing both TCP and UDP DNS requests between two DNS servers. Which is working fine except for- in our DN...
application delivery
devops
iRules
management
security
TMOS
TMSH
Cory_50405's avatar
Cory_50405
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Feb 25, 2014

Were you attempting this with a GTM iRule? If so, try using an LTM iRule (system processes LTM iRules very early in the process) and apply to your listener virtual server. This will be processed far before SNAT. Your trigger should be 'when DNS_REQUEST'