# Adding a Server Black List

To configure a new DNS black list for the server, or edit an existing black list, enter the following information and click Save.

Name. Enter a display name that will be used to identify the black list in log lines. This can be any name that you want, and does not have to correspond to the actual name of the black list.

Server. Enter the domain name or IP address of the DNS server to contact for black list queries. By default, this field contains a asterisk ( * ) for all default and new black lists. When an asterisk is entered, the default IMail Server DNS is used for black list queries. The default DNS server relays the DNS query to the DNS server for the black list. Therefore, if you enter an asterisk, you do not need to enter the IP address or domain of the black list.

Query Domain. The domain to query in the zone file. This name usually matches the server domain name. However, sometimes a black list will contain multiple zones to query on the same server, so the server name and the query domain will be different. The only way to know this is to read the documentation for the black list being used.

Type. The type of lookup that the black list performs. Select from the following types::

- ADDR (address). Uses a message's FROM address to determine if the message is spam.

- DNS. Checks the IP address of the connecting SMTP server against spam databases to determine whether the message is spam. If the IP address is listed in one of the black lists databases, the message is identified as spam.

- HELO. Checks the domain supplied in the HELO or EHLO command to determine whether to accept the message. The host name that is given in the HELO/EHLO command must match the IP address.

- RHS (right-hand side). Checks the information following the @ symbol supplied in the MAIL FROM command to determine whether the message is spam.

Enabled. Select this setting in order for the black list to be available for use by hosts. If a black list is disabled, it will not appear on the Host Black Lists page, but will still be displayed on the Server Black List page.

TCP/IP First. Identifies black lists that require the use of TCP to query the black list.

Note: It is up to the administrator to know whether a black list uses UDP or TCP protocol

Related Topics:

Server Black Lists