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Marcus_Hong_Yu's avatar
Marcus_Hong_Yu
Icon for Nimbostratus rankNimbostratus
Jun 13, 2017

RESOLV::lookup not able to pick resolved IP from DNS query answer

I recently used an irule on LTM to do DNS query for traffic forwarding. I used RESOLV::lookup in the irule to go against my DNS server and use resolved IP as pool member IP to establish the connectio...
application delivery
iRules
LTM
Marcus_Hong_Yu's avatar
Marcus_Hong_Yu
Icon for Nimbostratus rankNimbostratus
Jun 13, 2017

---following is my irule, It seems [RESOLV::lookup @$dns -a ";] is returning empty, my log has records " IP = "-------

 

when CLIENT_ACCEPTED { set dns 10.1.1.1 log local0. "SN dns => $dns" set dest [lindex [RESOLV::lookup @$dns -a ";] 0] log local0. " IP = [RESOLV::lookup @$dns -a ";]"

 

if {$dest eq ""}{ log local0. "No valid IP resolved" reject } else { node $dest 443 log local0. "SN Return IP=> $dest" } }