RDNS in windows 2008

[haniis]

Dear all,
we are an ISP, One of our clients Complain that he can not send an email to some emails, after checking this issue I found that I didn't do RDNS on our DNS and I did and it works localy from the server it convert the ip to FQDN but from the clients sites it does not . what can we do to solve this problem.

 

[baddos]

All public IP addresses should have reverse DNS entries. If you are re-allocating a subnet to your customer, you can provide dns services for them or let their DNS server do the work.

If it's a small customer with a couple of addresses, just make up some rdns entries for those addresses.

People will sometimes block email servers that do not have reverse dns entries to prevent receiving spam from unauthorized and/or unknown email servers that just sprang up for the purposes of sending spam.

 

[haniis]

Thanks,
the problem that our public dns couldn't allocate our FQDN by IP address.
I mean when I use ADSL from onther ISP and do nslookup
>Mail IP address
>*** cdns1.****.** can't find our mail IP: Non-existent domain.
may be I need to open some ports for that or why other public dns couldn't find our mail by ip.

 

[haniis]

Thanks,
the problem that other public dns couldn't allocate our FQDN by IP address.
I mean when I use ADSL from onther ISP and do nslookup
>Mail IP address
>*** cdns1.****.** can't find our mail IP: Non-existent domain.
may be I need to open some ports for that or why other public dns couldn't find our mail by ip.

 

[baddos]

You need to check with your ISP then, as they are probably doing your reverse dns.

 

[haniis]

I told you that we are an ISP, so we have our public DNS.

 

[baddos]

Do you have a directly allocated netblock? You may very well have your own DNS servers, but you may not be the authority for reverse dns of that netblock.

 

[haniis]

what is netblock?

 

[haniis]

Dear Baddos,
sorry I understand you, you are right. I have ip network/28
so how to give authority for reverse dns of that netblock. on windows server 2008

 

[baddos]

You cannot, that is a re-allocation provided to you by your ISP. You will need to contact them and have them setup their DNS for reverse dns on that netblock, or have them point it to your DNS server.