reverse dns configuration for IPV4, IPV6+ dns+ mail ?
pierre at couderc.eu
Mon Jun 19 07:44:28 UTC 2017
On 06/19/2017 01:05 AM, Reindl Harald wrote:
> Am 18.06.2017 um 17:38 schrieb Matus UHLAR - fantomas:
>> On 18.06.17 16:26, Mark Elkins wrote:
>>> Put two reverse records in both the IPv4 and IPv6 reverse zones....
>>> in the "125.124.123.in-addr.arpa" zone:
>>> 126 IN PTR mail.xxx.com.
>>> 126 IN PTR ns.xxx.com.
>> while this is possible, it's not always a good idea.
>> One reverse record is enough in most cases you need reverse DNS.
>> (which mostly means, for outgoing mail)
>>> Nothing wrong with a machine (or interface on a machine) having more
>>> than one name for the same address. List them all in the reverse
>>> configuration. After all, a NS record usually has at least two
>>> records ;-)
>> there are cases when having two reverse records is misleading
> it's nearly always misleading and results in randomness on the
> receiving server which name get logged and if A/PTR matches
> normally you should always have:
> * IP with *one* PTR
> * the A-Record for the PTR matches
> * smtp_helo_name of your MTA matches the same name
This is clear in IPV4 but what about IPV6 ?
If I declare xxx.com bind :
mail A 184.108.40.206
mail AAAA 2a01:e34:xxxx:xxxx:xxxx:xxxx:1122:3344
ns A 220.127.116.11
ns AAAA 2a01:e34:xxxx:xxxx:xxxx:xxxx:aabb:ccdd
What should I put for IPV4 reverse address : if I put mail.xxx.com, the
reverse address will not point on ns.xxx.com, and if put ns.xxx.com, the
reverse dns will not point on mail.xxx.com, and I shall have mail problem.
More information about the bind-users