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Greylisting Log Message

Lukas Plümper

New Pleskian
Hey,

I have a question regarding greylisting.

I activated greylisting on my mailserver and took a look in the logfiles.

The mail are temporary rejected with the following log message / statuscode:
451 4.7.1 Service unavailable - try again later;

Mails from my server to other servers are greylisted with messages like:
451 4.7.1 message delayed, see http://www.greylisting.org ;
452 Greylisted. Please try again after some time.
451 4.7.1 <E-MAIL-ADRESSE>: Sender address rejected: Greylisting in action. Please try again later.

Is it possible to change this log message at my server?

Best Lukas
 
Hi Lukas Plümper,

in order to avoid such issues, your mail - server should meet some standards. Please see http://www.greylisting.org/ as suggested and find :

What if my email was rejected and greylisting was mentioned as the cause?
This can happen for various reasons:

  • The MTA (mail transfer agent) / email ISP that you use to send email is not RFC 821 compliant. Contact your ISP.
  • The MTA is in some way misconfigured to not automatically retry email messages that gets rejected with the "try later"-message. Maybe it's timing is off and it retries immediately (which it shouldn't). Contact your ISP.
  • The recipient email server has got greylisting misconfigured, ie. an implementation that just doesn't let mails through even on later retries. Or maybe their error message is actually wrong: greylisting was NOT the reason your mail bounced - but something else.

As well you will find:

Can you remove me from your blacklist/greylist?
greylisting.org is JUST an information website. We are not responsible for maintaining any specific blacklists/greylists or for maintaining any whitelists.

You need to contact the actual operator of the mail server that rejecter your email and find out it was rejected (maybe they offer a whitelisting feature).


If you need help to configure your server, please include as well your operating system and configuration files


to get some suggestions. Especially for your mail - server configuration, it might be helpfull to visit


and include the results in your next post, so that investigations are easier for people willing to help you.
 
Hey,

the greylisting itself works fine.
The only thing i want to change is the "try later"-message.

The messages my server receives from other servers name greylisting as reason.
My log message just says "451 4.7.1 Service unavailable - try again later;".
Is this a problem?
Can i change this message?

As background information:
OS: Ubuntu 14.04 LTS
Plesk: Version 12
I use the integrated greylisting function from Plesk.

Best,
Lukas
 
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