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Forum Discussion

VFB's avatar
VFB
Icon for Cirrus rankCirrus
May 20, 2020

Return a Public IP to DNS query and send traffic to RFC1918

I created a WIP that I'd like when queried outside, it shows a public IP, but forward traffic to RFC1918 VIP. I created a NAT instance under delivery, but it doesn't work.

application delivery
BIG-IP DNS
LTM

2 Replies

  • KeesvandenBos's avatar
    KeesvandenBos
    Icon for MVP rankMVP
    Jun 02, 2020

    Hi,

     

    A WIP doesn't perform forwarding to a virtual server. It only answers with the DNS query with the correct IP address.

     

    Natting of your public ip to RFC1918 should be done by a firewall (or BIG-IP).

     

    Having RFC1918 address on your virtual servers and WIP serving public IP can be done by creating a dummy virtual server with the public IP address and use this virtual server in your wide ip pool.

     

    Cheers,

     

    Kees

  • Patrick_Brown's avatar
    Patrick_Brown
    Icon for Nimbostratus rankNimbostratus
    Jun 10, 2020

    I don't filly understand the question. Are you asking if you can answer a DNS query with a public answer when outside and private when inside? For use when a VPN is in place, for example. This is a use case that I use often. I use a DNS iRule and respond with a specific answer when certain conditions are met such as the IP address pool for my VPN.

     

    --Patrick