IPv6 woes - RFC

Sun Sep 19 09:25:44 UTC 2021

On 9/18/21 11:20 PM, Masataka Ohta wrote:
> Mark Andrews wrote:
> 
>  > There is nothing at the protocol level stopping AT&T offering a
>  > similar level of service.
> 
> Setting up reverse DNS lookup for 16B address is annoying,
> which may stop AT&T offering it.

How many mail servers are on the Internet today?  I don't know.  How  
many business customers (large and small) does AT&T have?  I don't know,  
and don't expect ever to know.  I assume by "16B" you mean "16 billion";  
if so, why did you select that value?

Based on the routing tables on my edge router for my existing  
connection-based allocation, I have a IPv6 address block with a /60  
prefix.  The AT&T SBCIS allocation for IPv6 is 2600:1700::/28  
(4.294.967.296 /60 prefixes), and the parent range is /12.  (In a prior  
message, someone mentioned that their customer was able to obtain a  
static /56 IPv6 address block.  Don't know how they did that, unless  
they are tunneling to a different provider like HE.)

AT&T does offer PTR records for IPv4 static addresses -- I have a set of  
static IPv4 addresses (which I pay for monthly) and one associated  
IN-ADDR.ARPA PTR record.  (I used to have *two* sets of static IP IPv4  
addresses -- both paid for monthly -- and two associated IN-ADDR.ARPA  
PTR records, but I released one of those sets when I discontinued my  
long-time DSL service with AT&T.)

 From the AT&T community forum, from two years ago, a moderator says  
this:  "IPv6 Its [sic] are assigned to your connection; IPv4 static IP  
blocks are assigned to you. This is why they still don't offer reverse  
PTR delegation."

What's missing?  A static prefix of IPv6, and one IP6.ARPA PTR record.  
I'm willing to pay for IPv6 static addresses, as long as I can get the  
one IP6.ARPA PTR record for my mail server.  Connection-based prefix  
would be fine, but I still need the PTR record to satisfy the Best  
Practices requirements for mail servers.

(Why do I run my own mail server?  When I started out with DSL many  
years ago, I used Pacific Bell's mail servers.  The IP reputation was to  
the point that mail from my systems was blocked by so many mail servers  
around the 'Net.  So, Postfix locally.  Never looked back.)