REVERSE DNS Practices.

Thu Mar 26 16:56:58 UTC 2009

on Thu, Mar 26, 2009 at 08:44:57PM +1100, Martin Barry wrote:
> $quoted_author = "Steven Champeon" ;
> > 
> > adsl.internode.on.net 
> > gaw.internode.on.net  
> > padsl.internode.on.net	
> > adsl.adelaide.on.net	
> > link.internode.on.net	
> > as0.adl2.internode.on.net	
> > lns1.adl2.internode.on.net	
> 
> ...and so on and so on.
> 
> You do realise that they were all infrastructure devices which would
> never send email? LNS isn't a big enough giveaway?

You do realize that we've seen mail from all of these, which is why
they're even on our radar, right? PaDSL is a VPN service. ADSL is a
pretty straightforward label. 'link'? Who knows? If you don't take the
time to think about your labeling and tokens, don't be surprised if
other people not privy to your internal naming scheme start guessing.

Especially if they're spewing spam and viruses like a firehose.

> > Oh, there's also 'static.internode.on.net', so the safe bet is to
> > assume that ALL of the rest are dynamic. Correct bet? Who knows.
> 
> That's a safe assumption.

Unfortunately, it's not. Even more unfortunately, we see more junk
from their generic statics than we do from their obvious dynamics. 

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