Regarding the reverse dns on virtualmin for mail that is delivered as spam

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1
SYSTEM INFORMATION
OS type and version rocky 9.3
Virtualmin version 7.10

now emails from postfix are delivered as spam because there is no reverse dns but reverse dns is configured for one ip only like 148.72.168.44 originated as reverse to mail.specialwebdesign.gr but the problem is that there is no reverse dns at all, is there somebody here that can help me how to configure the reverse dns for multiple domains so the mail will not be delivered and on many is rejected due that does’nt have PTR record.

if there is somebody that can help with that matter i will appreciate it

thank you

nikos sarantopoulos

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I think that summed it up for me.

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@nsarantopoulos

  • Contact your provider of the server (i am guessing velia.net) and ask them to setup a rDNS.
  • The rDNS must match your Virtuamin/Webmin server’s hostname.
  • You need your own dedicated IP address to be able to send emails from your servers (unless you use relaying provided by your server provider or use a relay provider like mailgun)
4

yes it might be that one, but what is going on with multiple domains without reverse dns only one domain can have reverse dns not multiple domain, in my case with my multiple domains what i have to do, i know that method but it does’nt help this way

thanks

nikos

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the rDNS is used to identify the server sending the email (i.e. virtualmin) , not the domain sending the email (i.e. clients)

1 Like
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so if it is like that what rDNS record i will create for me my primary domain on the server is specialwebdesign.gr

thanks

nikos

7

specialwebdesign.gr

no

It is the hostname for you virtualmin server, I am guessing server.specialwebdesign.gr

Tell your provider to set server.specialwebdesign.gr as the rDNS for 148.72.168.44

this assumes this is your server’s IP and this is your Virtualmin server’s hostname :smile:

To see what I mean:

https://mxtoolbox.com/diagnostic.aspx

And if you use specialwebdesign.gr you can see it shows me your servers hostname.

8

Strange its showing a godaddy IP
would that be right?

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no it is an ip provided by velia

10

They might resell.
godaddy has info on getting a reverse.

They do resell, never knew.
https://www.godaddy.com/en-au/reseller-program

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Nothing ptr records are ip based not domain based. Did you read the thread that @Stegan posted ? Think that explains it very well. @shoulders the ptr does not have to match the system hostname, all it needs to do is to resolve to the correct ip address

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Technically this is true, but If it does not match all of his email will get tagged as spam.

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Oddly my hostname is set to something different to the ptr and have no issues with email going to spam

1 Like
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15

Oh well whatever

16

This is not correct.
How is the 15 domain I have email getting delivered and 90% of the email going out will fail as most domains are shared hosting.

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it all about spam scores. Some servers will be more tolerant. For instance this error has a small negative effect:

SPF_HELO_NONE SPF: HELO does not publish an SPF Record

image

Also your hostname should match your rDNS as it is the whole purpose of the record to identify your server from the IP.

How is the 15 domain I have email getting delivered and 90% of the email going out will fail as most domains are shared hosting.

Not sure what you mean here. But maybe looking at the HELO handshake would help. This is a test for the domain specialwebdesign.gr

Connecting to 148.72.168.44

220 server.specialwebdesign.gr ESMTP Postfix [229 ms]
EHLO keeper-us-east-1d.mxtoolbox.com
250-server.specialwebdesign.gr
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH PLAIN LOGIN
250-AUTH=PLAIN LOGIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250-DSN
250-SMTPUTF8
250 CHUNKING [159 ms]
MAIL FROM:<supertool@mxtoolboxsmtpdiag.com>
250 2.1.0 Ok [158 ms]
RCPT TO:<test@mxtoolboxsmtpdiag.com>
554 5.7.1 <test@mxtoolboxsmtpdiag.com>: Relay access denied [161 ms]
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Shared host have 1 IP with one rDNS.
You show a negative score in would have no effect on being mark as spam, positive number add to the score and getting marked spam (5 default).
You statement that ALL of his email will get tag spam is incorrect that what I disagree with.
Test looks fine. Whats wrong there? That receiving not sending.

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Shared host have 1 IP with one rDNS.

Correct and normal

You show a negative score in would have no effect on being mark as spam, positive number add to the score and getting marked spam (5 default).

Wrong if it has a negative score, it is just that negative score. This was an example that the rDNS used

You statement that ALL of his email will get tag spam is incorrect that what I disagree with.

Ok :smile: fair enough , time will change where these indicators get more valuable

use https://www.mail-tester.com/

Reverse DNS lookup or reverse DNS resolution (rDNS) is the determination of a domain name that is associated with a given IP address.
Some companies such as AOL will reject any message sent from a server without rDNS, so you must ensure that you have one.
You cannot associate more than one domain name with a single IP address.

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I remember a time when a stock response was “I’ll pop that in the post” which overtime turned into “I’ll fax you” in turn that turned into “I’ll email you” so it’s only a matter of time that email will be retired in favour of a new medium so these indicators maybe just resigned to history