mailservertest can be used to make testing mail servers a bit easier. It is a short script written in Python. Here a few use cases.
You’ve just restarted a number of mail servers, and you want to verify that they are delivering mail
mailservertest my.email@example.com mail1.example.com mail2 mail3
This will send a test email to my.email@example.com through the four mail servers mail1, mail2, mail3 and mail4. Note that the full domain name needs to be specified for the first mail server mail1.example.com; afterwards the ‘example.com’ will be appended to the remaining mail servers. This will save you some typing.
When you run the command, you will see output like this:
mail1.example.com ... Connecting to server ... OK ... Sending the "helo" command ... OK ... Sending the email ... OK mail2.example.com ... Connecting to server ... OK ... Sending the "helo" command ... OK ... Sending the email ... OK mail3.example.com ... Connecting to server ... OK ... Sending the "helo" command ... OK ... Sending the email ... OK
The script verifies each step of the mail process for each server. Thus, you can see where in the process a problem is occurring. The -q option will turn off these messages, but error messages (if any) will still be shown.
The emails you receive will look like this
From: my.email@example.com Subject: MAILTEST: mail1 16:28:29 2013-12-08 To: my.email@example.com This is a test email Tag : MAILTEST: Date : 16:28:29 2013-12-08 All Recipients : my.email@example.com All Servers : mail1.example.com mail2.example.com mail3.example.com This Server : mail3.example.com ---------------------------------------------------- Sent from the script 'mailservertest' on the host 'Your-Host'
The Subject line was chosen to make it as useful as possible when viewed in an email client; it shows the server that sent the message and the time that the script was run. The “tag” MAILTEST can be customized using the -t option.
You need to verify that your mail server rejects invalid addresses during the initial connection.
If your mail server should reject email for invalid addresses, you can verify that with this command (shown with it’s output).
mailservertest -q noone@example.com mail1.example.com
ERROR: {'noone@example.com': (550, '5.1.1 <noone@example.com>: Recipient address rejected: User unknown in virtual alias table')}
First note that the -q option has removed the status output shown in the previous example. Only the error message is shown; and it verifies that the address is unknown.
You want to generate and inspect a bounce message
You may be able to generate an email bounce message by sending an email through one mail server functioning as an MTA (mail transfer agent) to a second mail server functioning as a MDA (mail delivery agent). If the MTA passes your message to the MDA, and the recipient address is invalid, the MDA will return a bounce message to the return address. Since in this case the recipient address and the return address must be different, we will need to use the -f option to mailservertest. The -f option sets the return address. By default, the recipient and return address are the same; this worked fine for the previous example, but not now.
mailservertest -f my-email@example.com broken-email@other.com mail.example.com
Here, broken-email@other.com is an invalid email address. We first send the email to our MTA mail.example.com. It will send the email to whatever mail server handles other.com. The email bounce will be sent to our email address my-email@example.com. Below is an example of what is returned.
Delivery has failed to these recipients or groups: broken-email@other.com The e-mail address you entered couldn't be found. Please check the recipient's e-mail address and try to resend the message. If the problem continues, please contact your helpdesk. Diagnostic information for administrators: Generating server: CASHUBE.grove.ad.other.com broken-email@other.com #550 5.1.1 RESOLVER.ADR.RecipNotFound; not found ##rfc822;broken-email@other.com Original message headers: Received: from mail.example.com (192.168.25.234) by CashubE.grove.ad.other.com (192.168.30.167) with Microsoft SMTP Server id 14.2.347.0; Sun, 8 Dec 2013 17:25:49 -0500 Received: from localhost (host.example.com [192.168.80.33]) by mail.example.com (Postfix) with SMTP id 2F1007F44 for <broken-email@other.com>; Sun, 8 Dec 2013 17:25:49 -0500 (EST) From: "my-email@example.com" <my-email@example.com> Subject: MAILTEST: mail 17:25:49 2013-12-08 To: <broken-email@other.com> Date: Sun, 8 Dec 2013 17:25:49 -0500 MIME-Version: 1.0 Content-Type: text/plain Message-ID: <e91f8c64-57e5-47db-a2bc-9857ce0c04f3@CASHUBE.grove.ad.other.com> Return-Path: my-email@example.com Reporting-MTA: dns;CASHUBE.grove.ad.other.com Received-From-MTA: dns;mail.example.com Arrival-Date: Sun, 8 Dec 2013 22:25:49 +0000 Original-Recipient: rfc822;broken-email@other.com Final-Recipient: rfc822;broken-email@other.com Action: failed Status: 5.1.1 Diagnostic-Code: smtp;550 5.1.1 RESOLVER.ADR.RecipNotFound; not found ForwardedMessage.eml Subject: MAILTEST: mail 17:25:49 2013-12-08 From: "my-email@example.com" <my-email@example.com> Date: 12/08/2013 05:25 PM To: <broken-email@other.com> This is a test email Tag : MAILTEST: Date : 17:25:49 2013-12-08 All Recipients : broken-email@other.com All Servers : mail.example.com This Server : mail.example.com ---------------------------------------------------- Sent from the script 'mailservertest' on the host 'host'
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