SUMMARY
How MailEnable determines local send and relay rights. MailEnable enumerates recipient (RCPT) requests in three logical rule blocks; Sender, Local Recipient and Relay Recipient Enumerations. MailEnable processes these rule blocks sequentially. These rule blocks and their processing are outlined under their respective headings.
DETAIL
Use the debug log in order to debug relay rights. The responses returned when enumerating rights are recorded with an appropriate description.
Use this description to determine if or how a relay request was handled by the
server.
SENDER
BLACKLISTING
Firstly, MailEnable processes rules that determine whether the sender of the message is banned from sending locally or relaying.
1. | MailEnable checks the Sender's address
and determines whether they are blacklisted and therefore banned from
sending locally or relaying. Debug Log Contains: Recipient Denied: %s is a blacklisted domain. |
Secondly, MailEnable enumerates the recipient address
and determines if the user is locally serviced.
1. | If the Recipient address is the postmaster,
access is granted. Debug Log Contains: Local Delivery: Address (%s) is local |
2. | If the Recipient address is defined in the
AddressMap as a literal address, access is granted. Debug Log Contains: Local Delivery: Address (%s) is local |
3. | If the Recipient address is defined in the
AddressMap as a catch all address, access is granted. Debug Log Contains: Address (%s) is to be delivered to Catch-All address. |
4. | If "Force Inbound Resolution" is set and the
Recipient address is to a locally serviced domain, access is denied.
Debug Log Contains: Local Delivery: Domain for (%s) is locally serviced, but recipient is not defined in address map. |
5. | If "Force Inbound Resolution" is not set and
the Recipient address is to a locally serviced domain, access is
granted. Debug Log Contains: Local Delivery: Domain for (%s) is locally serviced. |
Finally, MailEnable determines whether the recipient requires mail relay (i.e. the message is destined for addresses that are not locally serviced by this host). It does this using the following logic:
1. | MailEnable determines whether Overriding Relay
Access is enabled or disabled and grants or denies
accordingly. Debug Log Contains: Relay Denied: Server is configured not to allow relaying. (if relaying is disabled). |
2. | MailEnable determines whether "Allow Relay For
Local Sender Addresses" right has been set. This checks whether the Sender
address is defined in the address map table. Debug Log Contains: Relay Granted: %s is in local address map. |
3. | MailEnable determines whether "Allow Relay For
Privileged IP Ranges" right has been set. Debug Log Contains: Relay Granted: Sender IP (%s) is within an authorized IP range. |
4. | MailEnable determines whether "Allow Relay For
Authenticated Senders" right has been set. Debug Log Contains: Relay Granted: Sender has authenticated. |
5. | MailEnable determines whether "Allow Relay For
Anybody" right is set. Debug Log Contains: Relay Granted: Server is configured to allow anyone to relay. |
6. | All rules for relaying have now been processed
and no relay criteria could be met. So the server denies. Debug Log Contains: Relay Denied: Failed to meet all relay criteria. |
MORE INFORMATION
What is mail relaying?: http://www.mailenable.com/kb/content/article.asp?ID=ME020262
What are the best relay settings to use?: http://www.mailenable.com/kb/content/article.asp?ID=ME020001
How to test if the server is secured from abuse (Open Relay Test): http://www.mailenable.com/kb/content/article.asp?ID=ME020168
How does a server get blacklisted and how to get removed from blacklists?: http://www.mailenable.com/kb/content/article.asp?ID=ME020166
How to tell if the server been spammed through open relay?: http://www.mailenable.com/kb/content/article.asp?ID=ME020339
Product: | MailEnable (All Versions) |
Category: | Operation |
Article: | ME020034 |
Module: | SMTP |
Keywords: | Relay,local,sender,recipient,relaying,rights,sending,relays,relayed,SMTP |
Class: | INF: Product Information |
Created: | 8/07/2002 1:53:00 PM |
Revised: | Wednesday, May 4, 2016 |
Author: | MailEnable |
Publisher: | MailEnable |