GTM DNS ReverseLookup

Question

&nbsp;Hello everyone!!I was curious as to how the GTM gslb functions when executing a reverse lookup. I have a gslb url that fetches two ltm vips when I perform a nslookup, but when I try to perform a reverse lookup on the IP received, nothing like a failed result appears.Is this the gslb via GTM default behavior? or something not configured as is?&nbsp;

leslie_hubertus · Answer

Hey&nbsp;&nbsp;PowerRangers&nbsp;- I see nobody has answered this yet. I'll pin this to the top of the forum over the weekend to give your question better visibility.&nbsp;

kerry · Answer

Forward and reverse looks have nothing to do with each other.&nbsp; &nbsp;If luck the F5 GUI might add a record, but it does not mean things will work.&nbsp; Have a look underforward lookup:&nbsp; DNS&gt; zone&gt;zonerunner&gt;resource records: view = external (unless you use split DNS),&nbsp; names = FQDN domain, type=a/aaaa , names = host name/Wide IP names.&nbsp; &nbsp; &nbsp; you should see "0" TTL records if the Wide IP is defined.&nbsp;forward lookup&nbsp; DNS&gt; zone&gt;zonerunner&gt;&gt;resource records: view = external (unless you use split DNS),&nbsp; names = ...in-addr-arpa.&nbsp; &nbsp;you see PTR type records if things are defined.&nbsp; &nbsp;RDATA = FQDN.&nbsp;dig/nslookup&nbsp; &nbsp;FQDN F5-ip to test forward&nbsp; &nbsp;- i.e. nslookup f5.com 8.8.8.8&nbsp;dig/nslookup&nbsp; q=ptr (IP address in reverse).in-addr-arpa.&nbsp; F5-ip to test reverse&nbsp;i.e. nslookup -q=ptr 40.162.162.107.in-addr.arpa&nbsp;8.8.8.8&nbsp; &nbsp; (might have the incorrect syntax here)For forward lookup the domain above you need to define you as a subdomain using NX records. &nbsp;&nbsp;&nbsp;Same for reverse but is probably your IPS or who you got the IP address from is the DNS holder. &nbsp;I think you need a BGP AS number for this setup.&nbsp; &nbsp;i.e F5 the owner of&nbsp; *.162.107.in-addr.arpa&nbsp; would need to define NX record for “162” then then in thay zone can the PRT recodes be defined.I assume you talking about public DNS and not a private DNS. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

siona_somboba · Answer

seems like DNS "A" records missing for the 2 VS IP addresses in local DNS. please add and testif not please share output

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GTM DNS ReverseLookup

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