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IS_38885's avatar
IS_38885
Icon for Nimbostratus rankNimbostratus
Jan 20, 2009

Problems getting a simple name resolution "example" Irule to work

Hi,     I am trying to implement name resolution inside an iRule and I cannot get to work the simple example I find in the knowledge base.     The example is the following:  ...
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naladar_65658's avatar
naladar_65658
Icon for Altostratus rankAltostratus
Jan 22, 2009
The version number you are using looks good and from what I can tell, the code looks good to. I did check out the Wiki article on NAME::lookup and noticed this line and I thought I would point it out. Not all names have corresponding PTR records. Reverse resolutions are easily spoofed not guaranteed to be correct.

 

 

You might check out classless delegation and/or dangling CNAME pointers on Google and see if any of that information applies to your network setup. The results that you are seeing could very well stem from the way your particular DNS/Network setup is configured. Not that it is configured incorrectly, it may just not be able to follow the CNAME to grab the PTR record.... I think the method being used is referred to as a non-recursive query though I must admit my networking skills are a bit rusty at the moment.