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Same Reverse DNS entry for two IPs

Hi,

I have a query about a Reverse DNS and need a help of an expert.

Basically we have two mail servers with two public IPs.
A.A.A.A
B.B.B.B


A.A.A.A already got Reverse DNS entry with the leaseline provider for the domain mail.abc.co.uk.

Recently we have experience sending emails to AOL from public IP B.B.B.B and AOL has asked us to create a Reverse DNS entry to the IP B.B.B.B.

My query is, will it be a problem if I create a rDNS for B.B.B.B with the mail.abc.co.uk as there is an IP already (A.A.A.A) with a rDNS entry for the same domain. So if I asked other lease line provider to create an entry our scenario will be as the below.

Public IP     Reverse DNS Domain
A.A.A.A        mail.abc.co.uk
B.B.B.B        mail.abc.co.uk

My concern is whether two rDNS IP entries for the same domain will categorise our emails as spam and it will stop receiving emails to us?

Can an expert help me on this please?

Thanks in advance
Sx
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Tony J
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SHALINDRA

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Thanks Tony1044

What about if I create another DNS entries (A and mx) as mail1.abc.co.uk with our domain provider and create reverse DNS for mail1.abc.co.uk with the IP B.B.B.B, would this be the safe way?
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Ah crosspost.

The second way would be neater. Keep an eye on the priority of the MX records though. Do you want to use one server as primary and the second as a fallback (for receiving that is).
thanks Tony1044 and erniebeek. I understand this now.
Just for those who read this in the future, a small correction to Tony1044's first post (sorry again Tony).

A reverse DNS lookup does not resolve a DNS name to an IP address, it works the other way round. So the reverse lookup can't resolve to two IP addresses, that would be a 'normal' lookup.

More info on reverse DNS: http://en.wikipedia.org/wiki/Reverse_DNS_lookup
Sorry - that was a disconnect between brain and fingers. You are quite right about PTR records: They are indeed IP to name. Everything else stands true though :-)
But of course. I wouldn't dare to comment on the rest of post ;)