Chapter 6 – RouteFinder Software
Multi-Tech Systems, Inc. RouteFinderVPN RF760/660/600VPN User Guide (PN S000323D)
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Proxy > SMTP Proxy > SMTP SPAM Filtering
Recipient Black List
Enter a recipient’s email address to be blocked. Then, if the recipient’s email address matches any entry in
the list, the email will not be forwarded.
If all email from a domain is to be blocked, add this @ symbol before the domain name:
If you want to block all email from the domain
routefinder. yourdomain.com
, then add it as
@routefinder.yourdomain.com
Check for NULL Sender
If you check this option, email with an empty sender address sent to more than one recipient will not be
relayed.
Note:
If the email contains only one recipient ID, even if this option is checked, the email will be relayed to
the recipient, since it is legitimate to have NULL sender address in error.
Reverse DNS Test
If you check this option, the SMTP Proxy will try to resolve the domain name part of a sender’s email ID. If
it is resolved to an IP address, then the email will be relayed. If the sender’s name is in the Authentic List,
then the reverse DNS test will not be performed for the domain.
Bad Patterns in Sender/Recipient Address
Enter any pattern in an email address that you would like to block. Then both the sender and recipient
email addresses will be checked for these patterns. If the patterns match, the email will not be relayed.
Control Characters:
1.
Exclamation mark (!): Bypass the SPAM check for this entry alone.
Example: All email from or to the domain
abc.com
will be stopped except for
:
*@abc.com
2.
Asterisk (*): Stop all email from or to this domain.
Example: All email from or to the domain
abc.com
will be stopped.
*@abc.com
3.
Set ([…]): Stop all email from a set such as
@abc[0-9]*.com
.
Example: All email from or to the domains that include numbers in the first part of their
names such as
0, 234,
or
789023
will be stopped.
0.com
234.com
789023.com
4.
Question mark (?): Stop all email with a match zero or one occurrence of the preceding
character or set of characters.
Example: All email from or to the domains
abc.com
,
abc0.com
,
abc1.com
, …
abc9.com.
*abc[0-9]?.com
5.
Backslash (\): Literal expression of the following character (the following character is a
metacharacter):
@\[[0-9]{1-3}\[0-9]{1-3}\[0-9]{1-3}\]
The first two characters after the @ character \[ means take the literal value of the [
character.
Example: All email addresses with IP addresses like
username@[1.1.1.1]
will not be
allowed.
Note:
SPAM emails with percent-hack can be eliminated by adding *%* to the
Bad Patterns
list.
Maximum Mail Size Allowed
The size of each email will be compared with the Maximum Size entered here, and if the mail size is more
than the Maximum Size, then that mail will not be relayed. This check will be bypassed for users added to
the
SPAM Filtering Authentic List
(on this same screen).
Message Filtering
When
Message Filtering
is checked, the screen expands to display the following fields:
