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JAK
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Mar 11, 2016

GTM Wide-IP Question

Can the GTM be configured to handle an IP for the Wide-IP, vice a hostname request. For example, I hit the listener on 10.1.1.1 and configure the Wide-IP with the same ip 10.1.1.1, then globally balance that IP to send traffic to the available Virtual Server. Thanks, -JAK

 

3 Replies

  • By definition a Wide IP is a hostname - GTM processing gets triggered when the GTM receives a DNS request. In a production setup you would never receive a DNS request for 10.1.1.1 since there is no Top Level Domain there (unless .1 is now a valid TLD). Can you please clarify what you are trying to achieve?
  • JAK's avatar
    JAK
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    Thanks for replying raduioncu Scenario, entire Data Center goes down, when clients begin to come back online, they need to reach out to their DNS servers, DC, etc....but the local DNS servers are not avaialbe. So the idea was to provide a single Global IP for all clients to reach and be able to send the request to an available DNS server in a remote Data Center. This works fine using LTM, if the LTM is online at the local Data Center, but the scenario states the local LTM is down as well. The idea would be to have that IP globally held on the local GTM so it would know which LTM was available with online DNS servers. We could have the local GTM in an active/active pairing with a remote GTM, in case the local GTM is down as well. As I type this, it's starting to dawn on me why this might not be possible...so if we had a local GTM in active/active state with a remote GTM, they cannot share the same listener... Primary goal...configure all client with DNS (and eventually other required services such as NTP, syslog etc.) to use the SAME primary and secondary IP...regardless of site. Trying to avoid major routing manipulation by involving the GTM, however, we may only be able to do this with tunnels via WAN and interface based routing locally. -Jeff
  • You can't use DNS to resolve an IP address to another IP address, which appears to be your goal. It won't work, because the client will never make a DNS request to resolve an IP address, as it is already resolved.

     

    What you need to do is set up your network routing to anycast that address into your network - this is how google's 8.8.8.8 works for example. If you advertise 10.1.1.1 into your network in multiple places, and one falls off, then the network will route it to the other more remote one.