Mail server_Dovecot configuration_Testing Receiving - SomethingWithHorizons/mailserver GitHub Wiki

Verify whether dovecot has been correctly configured for retrieving mail.

After configuring dovecot, the mail server should be capable of receiving e-mails. In order to verify the configuration, swaks is used to mimic an external SMTP server by sending emails. By mimicking an external SMTP server, a variety of happy flow and error flow scenarios can be explicitly tested.

:warning: WARNING: These tests assumes availability of the test data imported earlier!

Procedure

0. Ensure swaks is installed on the system you are executed the tests from:

   # Clear the mail related log files
   apt install -y swaks
   

1. Clear the mail related log files to prevent possible false positive test results later:

   # Clear the mail related log files
   echo " " > /var/log/mail.log
   echo " " > /var/log/mail.err
   echo " " > /var/log/mail.info
   

2. Execute the following SMTP protocol tests (PASSED reflects correct operation):

   # Configure the ip address being used (to avoid having to retype it every time
   ip=<MAIL SERVER IP>
   
   # Test whether e-mails to a known user / known domain combination gets accepted
   swaks --to [email protected] --server $ip | grep "250 2.0.0 Ok: queued as" && echo "PASSED" || echo "FAILED"
   
   # Test whether e-mails to a known user/unknown domain combination get rejected
   swaks --to [email protected] --server $ip | grep "454 4.7.1 <[email protected]>: Relay access denied" && echo "PASSED" || echo "FAILED"
   
   # Test whether e-mails addressed to a known, specific, alias get accepted
   swaks --to [email protected] --server $ip | grep "250 2.0.0 Ok: queued as" && echo "PASSED" || echo "FAILED"
   
   # Test whether e-mails to a known, catchall alias get accepted
   swaks --to [email protected] --server $ip | grep "250 2.0.0 Ok: queued as" && echo "PASSED" || echo "FAILED"
   

   <MAIL SERVER IP> is local IP address (e.g. 192.168.1.x) of the mail server.

   :warning: WARNING: Don't use localhost (127.0.0.1), as this changes the server feedback!

3. Check the mail.log whether the aliases correctly got processed:

   # Test whether the known, specific, alias correctly got resolved (during step 1 execution)
   grep "to=<[email protected]>, orig_to=<[email protected]>" /var/log/mail.log && echo "PASSED" || echo "FAILED"
   
   # Test whether the known catch-all alias correctly got resolved (during step 1 execution)
   grep "to=<[email protected]>, orig_to=<[email protected]>" /var/log/mail.log && echo "PASSED" || echo "FAILED"
   

4. Execute the SMTP protocol scenario that cannot be executed having a catch all alias active:

   # Open mysql
   mysql
   

   -- Remove the catch-all alias from the MySQL database
   DELETE FROM `mailserver`.`aliases` WHERE `source` = '@example.org';
   exit;
   

   # Configure the ip address being used (to avoid having to retype it every time
   ip=<MAIL SERVER IP>
   
   # Test whether e-mails to an unknown user / known domain get rejected
   swaks --to [email protected] --server $ip | grep "550 5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table" && echo "PASSED" || echo "FAILED"
   

   <MAIL SERVER IP> is local IP address (e.g. 192.168.1.x) of the mail server.

   :warning: WARNING: Don't use localhost (127.0.0.1), as this changes the server feedback!

   # Open mysql
   mysql
   

   -- Restore the catch-all entry:
   INSERT INTO `mailserver`.`aliases` (`domain`, `source`, `destination`) VALUES ('example.org', '@example.org', '[email protected]');
   exit;