PTR records for IPv6

Mohacsi Janos mohacsi at
Tue Sep 3 13:14:30 CEST 2013

On Tue, 3 Sep 2013, Mikael Abrahamsson wrote:

> On Mon, 2 Sep 2013, Mohacsi Janos wrote:
>>> Yes, but we must not forget temporary addresses. If the MTA has temporary 
>>> addresses, then it will prefer them for its smtp sessions. So, one should 
>>> either disable temporaries on all MTAs or use DNS dynamic updates. I think 
>>> that it would be much wiser to deprecate PTR checks for IPv6.
>> Why would you use temporary address on a defined SMTP server?
> Mostly because it's on by default. Even if you configure a static address and 
> default gw, as soon as the system sees RAs it might start to use SLAAC based 
> privacy addresses for outgoing connections. I've already seen this happen 
> once, which caused problems sending mail to google.

I think it is Configuration problem on SMTP server.

More information about the ipv6-ops mailing list