Chapter 34 Anti-Spam
ZyWALL USG 50 User’s Guide
577
The following table describes the labels in this screen.
Table 169
Configuration > Anti-X > Anti-Spam > DNSBL
LABEL
DESCRIPTION
Show Advance
Settings / Hide
Advance Settings
Click this button to display a greater or lesser number of configuration
fields.
Enable DNS Black
List (DNSBL)
Checking
Select this to have the ZyWALL check the sender and relay IP
addresses in e-mail headers against the DNSBL servers maintained by
the DNSBL domains listed in the ZyWALL.
DNSBL Spam Tag
Enter a message or label (up to 15 ASCII characters) to add to the
beginning of the mail subject of e-mails that have a sender or relay IP
address in the header that matches a black list maintained by one of
the DNSBL domains listed in the ZyWALL.
This tag is only added if the anti-spam policy is configured to forward
spam mail with a spam tag.
Max. IPs
Checking Per Mail
Set the maximum number of sender and relay server IP addresses in
the mail header to check against the DNSBL domain servers.
IP Selection Per
Mail
Select
first N IPs
to have the ZyWALL start checking from the first IP
address in the mail header. This is the IP of the sender or the first
server that forwarded the mail.
Select
last N IPs
to have the ZyWALL start checking from the last IP
address in the mail header. This is the IP of the last server that
forwarded the mail.
Query Timeout
Setting
SMTP
Select how the ZyWALL is to handle SMTP mail (mail going to an e-
mail server) if the queries to the DNSBL domains time out.
Select
drop
to discard SMTP mail.
Select
forward
to allow SMTP mail to go through.
Select
forward with tag
to add a DNSBL timeout tag to the mail
subject of an SMTP mail and send it.
POP3
Select how the ZyWALL is to handle POP3 mail (mail coming to an e-
mail client) if the queries to the DNSBL domains time out.
Select
forward
to allow POP3 mail to go through.
Select
forward with tag
to add a DNSBL timeout tag to the mail
subject of an POP3 mail and send it.
Timeout Value
Set how long the ZyWALL waits for a reply from the DNSBL domains
listed below. If there is no reply before this time period expires, the
ZyWALL takes the action defined in the relevant
Actions when
Query Timeout
field.
Timeout Tag
Enter a message or label (up to 15 ASCII characters) to add to the
mail subject of e-mails that the ZyWALL forwards if queries to the
DNSBL domains time out.
DNSBL Domain
List
Add
Click this to create a new entry.
19216811.live