Forum Discussion

dcours_21197's avatar
dcours_21197
Icon for Nimbostratus rankNimbostratus
Oct 03, 2013

Problem using DNS::return in a GTM iRule

Hello, I'm trying to have a wide IP on my GTM return a NXDOMAIN response if the IP receiving the query is in a specified list. Since I want this to only apply to queries for a given wide IP, I'd l...
application delivery
devops
iRules
Mike_61663's avatar
Mike_61663
Icon for Cirrus rankCirrus
Feb 03, 2014

You'll have to do this as an LTM iRule as those DNS functions don't work as GTM iRules.

 

GTM iRules can return CNAME and A records utilising the "cname" and "host" commands respectively, but they can't return NXDOMAIN afaik.

 

If you want to only do this behavior for particular FQDNs (WideIPs) then simply add an additional condition to your iRule logic e.g. if { ([DNS::rrtype] eq "A") and ([DNS::rrname] eq "wideip.domain.com") } {

 

(just remember - to use this as an LTM iRule, make sure you enable a DNS profile on your GTM listener(s))