How to prevent specific mail from being blocked by an RBL list in Antigen (905960)



The information in this article applies to:

  • Sybari Antigen 8.0 for Microsoft Exchange
  • Sybari Antigen 8.0 for SMTP Gateways
  • Sybari Antigen 8.0 for Microsoft SharePoint Portal Server
  • Sybari Antigen 8.0 for IM
  • Sybari Antigen 7.5 for Microsoft Exchange
  • Sybari Antigen 7.5 for SMTP Gateways

INTRODUCTION

This article describes how to prevent mail from being blocked by a Real-time blackhole (RBL) list.

MORE INFORMATION

You can use either of the two methods that are described in this section to prevent mail from being blocked by a RBL list.

Method 1: Use an Allowed Mailhosts list

When you use an Allowed Mailhosts list, mail from "safe" mailhosts will not be filtered by Antigen RBL Filtering. By default, the Allowed Mailhosts list that is included with Antigen includes "*sybari.com." To edit the Allowed Mailhosts list, follow these steps:
  1. Start the Sybari Client (SybariClient.exe).
  2. In Shuttle Navigator, click Filtering, and then click Filter Lists.
  3. Click Allowed Mailhosts, click the list that you want to edit, and then click Edit/Import.

    Note To create a new list, click Allowed Mailhosts under List Types, and then click Add.
  4. Click Add, type the name of the domain that you want to allow, and then press ENTER.

    You can enter a domain name or an IP address. Make sure to type a wildcard character (*) before each domain name. For example, type *domain_name.com.
  5. In Shuttle Navigator, click Settings, and then click General Options.
  6. Type a number that is appropriate to your organization's messaging topology in the Maximum Allowed Mailhosts Lookup box.

    Type a number that is equal to the number of relay servers that have public IP addresses in your organization plus one. For example, if your organization has two public IP addresses that an e-mail message can pass through, type 3 in the Maximum Allowed Mailhosts Lookup box. When you type 3, the last external IP address will be checked against the Allowed Mailhosts list. The internal public IP addresses may be for relay servers that are located inside the perimeter network (also known as DMZ, demilitarized zone, and screened subnet).
  7. In the General Options panel, click Skip Content Filtering for Allowed Mailhosts.
  8. Save your changes.
Note The entries in the Allowed Mailhosts list will not override entries in the Rejected Mailhosts list.

Method 2: Use a Sender Whitelist

You can use Sybari Spam Manager and Advanced Spam Manager to create and to maintain lists of safe e-mail addresses and of safe e-mail domains. These lists are named Sender Whitelists. Antigen compares the address in the "From" field in the MIME header of an e-mail message against the Sender Whitelist. If the e-mail address or the e-mail domain appears in the Sender Whitelist, Antigen bypasses filtering and spam scanning for the e-mail message.

To create a Sender Whitelist, follow these steps:
  1. Start the Sybari Client (SybariClient.exe).
  2. In Shuttle Navigator, click Filtering, and then click Filter Lists.
  3. Under List Types, click Sender Whitelists.
  4. Under List Names, click Add, type a name for the new list, and then press ENTER.
  5. Click the new list, and then click Edit/Import.
  6. Click Add, type the e-mail address or the domain name that you want to add to the Sender Whitelist, and then press ENTER.

    Use the following format for user addresses:

    user@domain_name.com

    Use the following format for domain names:

    *domain_name.com

    Note If you are adding more than one entry, press ENTER after you type each entry.
  7. Click OK.
  8. To enable the Sender Whitelist that you created, follow these steps:
    1. In Shuttle Navigator, click Filtering, and then click Sender Whitelists.
    2. In the right pane, click the Sender Whitelist that you created, and then click Enabled under List State.
    3. Under Whitelist types, select the type of filtering that you want Antigen to skip for messages that are filtered by the Sender Whitelist. For example, click to select one or more of the following check boxes:
      • Spam Scanning
      • Mailhost Filtering
      • Content Filtering
      • Keyword Filtering
      • File Filtering

Modification Type:MajorLast Reviewed:10/6/2005
Keywords:kbtshoot KB905960