automatic reverse and forwarding zones

[Grant Taylor]

On 10/27/22 1:24 PM, Marco wrote:
> At least for IPv4, there are servers that reject connections from 
> IPs that don't have a reverse zone with PTR record.

Please elaborate.

I've not heard of (unspecified type of) servers rejecting connections 
because of the lack of a PTR record.

I have heard of mail servers /accepting/ a /TCP/ /transport/ connection 
layer but /rejecting/ email at the /SMTP/ /application/ layer for the 
lack of a PTR record.

IMHO mail servers are not in scope for a $GENERATE style flood filling 
of a zone.  Rather they are in scope for very specifically generated 
AAAA records.

> That is the only reason that I see for that.
> Most ISPs do it.

I'd say that /many/ ISPs populate in-addr.arpa zone(s) for IPv4.  --  I 
still run across IPv4 addresses that don't have PTR records way more 
often than I think is reasonable.

I've seen no evidence that ISPs also populate ip6.arpa zone(s) for IPv6 
in a similar way.  Not the least of which are some of the reasons called 
out in this thread.



-- 
Grant. . . .
unix || die

-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 4017 bytes
Desc: S/MIME Cryptographic Signature
URL: <https://lists.isc.org/pipermail/bind-users/attachments/20221027/56d1ed6a/attachment.bin>