Reverse DNS does not match SMTP Banner

Reverse DNS does not match SMTP Banner

Linode 4GB

CentOS 7

Vesta CP

I am dummy.

And again - I am dummy!

Please in human language without abstractions :-)

Thank you!

Please do not send me to https://www.linode.com/docs

https://www.linode.com/docs/email/running-a-mail-server

and other articles.

I have read it but I do not understand.

No SSH!

FTP only.

No Postfix.

Exim only.

10 Replies

Y my dear pclissold.

I need free help.

You need to give us more information.

What domain are you trying to do this with?

What IP does your mail server listen on?

Sorry.

I would not like to publicly disclose the domain and IP.

This is my domain hosted at Linode server.

I am not new with Internet things but never have had VPS.

I have dealt with shared hostings only since 1996 :-)

My first hosting in USA was Nathan Murray's Stormwire in 2001.

I have choosed Linode because it is an old company since 2003: http://web.archive.org/web/200306140843 … linode.com">http://web.archive.org/web/20030614084310/http://www.linode.com

Thank you!

I have found this advice at https://forums.cpanel.net/threads/warni … er.154625/">https://forums.cpanel.net/threads/warning-reverse-dns-does-not-match-smtp-banner.154625/
> You have two options:

1 Change the PTR pointer to the name of the server.

2 Rename the server to what the PTR is.

Not sure what does it mean, where and what it should be done.

The domain name configured by the mail server does not match the domain name set in reverse DNS. You can change the settings in the mail server to ignore such errors or set your reverse DNS to match your hostname.

Do one of the following, two, or both (as long as they come out the being the same host name)

Setting the reverse DNS : https://www.linode.com/docs/networking/ … everse-dns">https://www.linode.com/docs/networking/dns/setting-reverse-dns

Setting the system's hostname: https://www.linode.com/docs/getting-sta … e-hostname">https://www.linode.com/docs/getting-started#setting-the-hostname

  • or -

Disable postfix reverse lookup (warning, it is said to offer some spam control leaving it on…I find it just causes ipv6 issues): http://www.postfix.org/postconf.5.html# … t_hostname">http://www.postfix.org/postconf.5.html#rejectunknownclient_hostname

The above is based on very limited information given in the original post and could be considered a guess. It's a common error though.

Thank you!

I do not have Postfix. I have Exim only.

As sayed before - I have read these articles and asked not to send me to them. I do not understand. This is why I ask here :-)

> Please do not send me to https://www.linode.com/docs

https://www.linode.com/docs/email/running-a-mail-server

and other articles.

I have read it but I do not understand.

Do the same but follow Exim's instructions for the localhost. Same problem different software. Or just set your reverse DNS to match what pops out when you run the hostname command at the prompt

[smyo@sv5 smyo-beta]$ hostname

sv5.domain.com <-That should be your reverse DNS set up in the Linode manager.

If you cannot read the docs you are in for a world of hurt!

Thank you!

Sorry, I do not understand what exactly should I do now.

If a dummy would ask me I would help him in this way:

Step #1 - Open file aaa.txt in directory bbb in your text editor (Notepad++)

Step #2 - Find line number 50 and replace XXX with YYY

Step #3 - Save your aaa.txt file

Step #4 - Reboot server

DONE!

I can read the docs but they are not clear for me.

And there is a lot of garbage texts.

People love to explain details and educate others.

Thank you!

Again I am forced to ask for payed help or contact my server admin friends :-)

I am too silly.

@gtp9/?R℉:

Again I am forced to ask for payed help or contact my server admin friends :-)
This is the correct solution for you. In the spectrum of problems you will have trying to run an email server this is an exceptionally simple one to solve. If you can't figure out the docs for this with several people pointing you in the right direction then you are in way over your head.

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