IPv6 Debugging Gotcha

I was trying to use the ColdFusion 8 Ajax debugger and could not get it to pop up, despite having that option enabled and my IP address ( in the debug IP address list. Eventually I discovered (by mistake) that if I used “” in the URL then debugging worked, but if I used “localhost” it did not. The problem? IPv6 (used by default in Vista), where localhost maps to “0:0:0:0:0:0:0:1” instead of “”, causing the IP address to not match what was in the allowed debug IP address list. The solution is to simply add “0:0:0:0:0:0:0:1” to the list of allowed IP addresses (or just access CF Admin using “localhost” and click “Add Current” which will add that address). We’ll fix this by the time we ship CF8 so that 0:0:0:0:0:0:0:1 is also a default, but if you are using the ColdFusion 8 public beta you’ll want to add this manually for now.

7 responses to “IPv6 Debugging Gotcha”

  1. todd sharp Avatar
    todd sharp

    Noticed this myself last weekend. "::1" appears to work too – thats what CF added when I clicked "add current" – so not knowing much about IPv6 I assume that is a valid shortcut?

  2. Ben Forta Avatar
    Ben Forta

    Todd, yes, that is indeed a valid shortcut.
    — Ben

  3. Benjamin Avatar

    I’ve noticed the same to be true under CFMX 7 and vista.

  4. Ben Forta Avatar
    Ben Forta

    Benjamin, as CFMX7 supports IPv6, that would indeed be the case. Thanks for pointing that out.
    — Ben

  5. Jason Troy Avatar
    Jason Troy

    Well there ya go (I just disabled IPv6)

  6. Hemant Avatar

    We may add the localhost IPv6 address by default just the way we add 127.0.01 currently in CF8.

  7. Joris de Beer Avatar
    Joris de Beer

    I’ve noticed that having IPV6 on, means that the developer version will count that as a separate IP address from your IPV4 address, so you are more likely to run into the License Exception.
    This is on a Mac (10.5.x)

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