No reverse name ptr for your sender ip

Again, the remote host is looking at this generic DNS and assuming that generic means "random home user", which in turn means you're more likely talking to a bot than an actual mail server. I know this is an old conversation, I just wanted to add my two cents worth of summary Most of the reverse checks have this in common: they check something from both the forward DNS domain and the reverse domain eg. These two domains are not usually controlled by the same entity, especially when one is trying to masquerade as a different domain.

Whereas with legitimate situations, you can ask the other domain administrator to make the appropriate change on their side as well. Home Questions Tags Users Unanswered. Does a PTR record prove anything about the sender's email domain? Ask Question. Asked 8 years, 1 month ago. Active 3 years, 9 months ago. Viewed 6k times. Peter Mortensen 2, 5 5 gold badges 22 22 silver badges 24 24 bronze badges. Jake Jake 5 5 gold badges 19 19 silver badges 47 47 bronze badges. Want to say a big thank you to all who spent time posting answers and comments at length to help me. I would give more up votes if I could.

Now back to your original question: Receiving mail servers check none, one, many or all of the following: Is the HELO name equal to the hostname A record? Does the sender's domain have at least one MX record? Reverse DNS must be in the form of a fully-qualified domain name.

Reverse DNS containing in-addr. Reverse DNS consisting of IP addresses are also not acceptable, as they do not correctly establish the relationship between an IP address and its associated domain. Sorry, I think I am too dumb to understand. So what even if the forward and reverse DNS matches? It doesn't say anything about the sender or the sending MTA. I can set up mydomain. So I can set up an honest PTR for x.

It says the server admin had a clue how to set up properIP networks - which is different from "some bot on a home machine just being spamming over an end user ADSL connection". TomTom I know I just have to do it. But I am still not convinced of the value of checking the PTR!! Must be missing some important link. I sent the reasoning AOL gives for checking this information. The value is that it tells the receiving server that the sender is established properly.

Other than that, it's a best-practice.

It proves that you are who you say you are. Update: Some history and clarification. You need to know that none of this is guaranteed to work. It doesn't stop me from sending as me gmail. Which incidentlaly is the job of SPF. So why doesnt it simply just check the SPF for gmail.

Reverse DNS White Labeling — Hello, My Name Is…

Because as email goes, SPF is relatively new. That's what I don't understand too. In practice, my outgoing and incoming could both be different. It is not, as the domain in the email has nothing to do with the host name. Hosts may send tons of different domomains from one computer. The PTR just has to point back to the name the hosts identifies ITSELF as not the email - otherwise it is assumed you area dial up host and people dont want to deal with botnet spam from private computers via DSL, pretty much. Zen Software Knowledge Base.

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Does a PTR record prove anything about the sender's email domain? - Server Fault

We have started receiving bouncebacks from some mailservers I have multiple domains setup in MDaemon. Which should I use for my rDNS entry? Ask Question. Asked 9 years, 5 months ago. Active 6 years, 3 months ago. Viewed 40k times.

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Sometimes mails will be rejected by the receiving side with the following message: This is the mail system at host mail. For further assistance, please send mail to postmaster. The mail system NS dns2. Any idea on how to fix this? Do I have to contact my ISP? The short version - yeah you need to contact your ISP and ask them to change the record. Charles Charles 4 4 silver badges 9 9 bronze badges. Precisely what I was about to say.

One thing: do the ISPs change the ptr record on the client request?

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A lot of times at least here in Italy they tell you that they can delegate the entire zone, but not change one single record. How it works in other countries? That is a good question which I am honestly not positive on, I used to work for a large mail hosting corporation here in the US and we dealt with similar issues to yours with clients all the time.

I asked the ISP, but being a bit slow haven't gotten a response yet. I would check out this link, amset. I don't really understand why they would refuse unless it is a shared IP, but if they really do then you can look at the option the article gives you.