Setting up reverse DNS correctly

[John Coutts]

In article <cd4233$cen$1 at sf1.isc.org>, cching at mqsoftware.com says...
>
>I recently had a sent e-mail to comcast.net bounced back to me saying
>something about "only valid hosts may send."  Tracking it down, I
>found (using www.dnsreport.com) that I might not have reverse DNS set
>up correctly for my domain name.  Could somebody help me out with
>this?  Here is the db file for the domain (unaltered).  The named
>daemon is bind 9 (not sure of the exact version).
>
>I have tried a few things in the last couple of days, but haven't
>gotten dns report to tell me it's set up right, so I've set it back
>the way it was originally.  Thanks for any help and let me know if I
>need to post any other information!
>
>Cheers,
>Craig
***************** REPLY SEPARATER ********************
Unless your ISP (XO Communications) has delegated the authority for your IP 
range to you, there is little you can do to get correct reverse lookup. For 
further info see:

   http://server2.yellowhead.com/reverse.htm

Having said that, most MTAs that check for PTR, only check for the existence of 
a PTR record, and not that it reports correctly. [67.107.38.61] responds with 
[61.32/27.38.107.67.in-addr.arpa] on a reverse lookup. The practice of multiple 
domain names using the same IP address makes verifying the domain name by 
checking the PTR record virtually impossible, because a lot of software does 
not check for more than 1 PTR record.

Most ISPs won't delegate authority for a small number of IP addresses. From the 
looks of it, you have a 32 address block, which they should delegate, although 
they may ask for a small fee.

J.A. Coutts