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PowerRangers's avatar
PowerRangers
Icon for Cirrostratus rankCirrostratus
Mar 06, 2024

F5 DNS Reverse Lookup - Query Refused

Hello everyone, 

 

I have a wide IP configured on the F5 DNS/GTM and I see some issues with the reverse lookup behavior. 

 

I have Internal DNS pointing CNAME to F5 DNS Listener and resolving an IP using Pool. 

 

Example: 

 

www.example.com(infoblox) >> CNAME www.gslb.example.com ( F5 WIP NAME) >> IP address ( F5 DNS WIP Pool )

 

When I do nslookup www.example.com I see its returning the IP. but when I use the Ip address in the nslookup I see " can't find 199.222.xx.xx: Query refused"

 

Wanted to know why F5 DNS is giving the Query Refused. Do I need to change anything in my settings?? 

application delivery

1 Reply

  • zamroni777's avatar
    zamroni777
    Icon for MVP rankMVP
    Mar 08, 2024

    just like forward query, you need to properly setup the name servers based on the hierarchy of the reverse lookup.

    example for 192.168.10.1 ( 1.10.168.192.in-addr.arpa), your need to setup name servers of 10.168.192.in-addr.arpa and 168.192.in-addr.arpa and add ns entry of them in local dns servers.