This article applies to:

• Trustwave MailMarshal (SEG)

Question:

• How do I change the allowed Hop Count value in MailMarshal SMTP?
• Log message: Hop count limit exceeded.
• Receiver log shows messages to local domains being refused with "554 Too many hops"

Background:

By default MailMarshal enforces a SMTP hop count limit of 25 hops. Any message that has more than 25 Received: entries in the headers is suspected of being looped between servers.

Before changing the limit, examine email headers and routing to verify that the large number of hops is legitimate. It is extremely rare for more than 25 hops to be required.

Procedure:

Warning: Using the Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Trustwave cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Make sure that you back up your Registry prior to making any changes.

To change the hop count limit:

• In MailMarshal 10.0 and above, open the Management Console and navigate to Advanced Settings. Add a new value:
  • Name: Receiver.MaxHopCount
  • Type: Integer
  • Value: The required number of hops
• In MailMarshal 8.X and below, open the Registry Editor on the Array Manager. Within the base registry key, navigate to \Default\Receiver
  • In version 8.X: HKEY_LOCAL_MACHINE\SOFTWARE\Trustwave\Secure Email Gateway\Default\Receiver
  • For information about the registry location for each version, see article Q10832.
  • Enter the value as a new DWORD value named MaxHopCount (Required number of hops, as Decimal value).
• Save your registry settings or configuration settings.
• Commit the configuration changes and restart the MailMarshal Receiver service on each node.