Negative results are cached for exactly the same reasons as positive ones - performance. If a domain is unresolvable, then it's very likely that in 5 minutes time it will still be unresolvable, so the negative result is stored for a period of time to remove the need to do the lookup again.
As Mat stated, negative results are usually cached for shorter periods of time. However, unless you have some way of getting those DNS servers flushed, then you're a bit stuck. It should be noted that the servers that are causing the problem may not be the ones from that IP Config - those DNS servers will be carrying out their lookups against another set of DNS servers. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To view this discussion on the web visit https://groups.google.com/d/msg/google-appengine/-/VmvidENtczIJ. To post to this group, send email to google-appengine@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
