Symantec 10765539 - Mail Security For SMTP, Руководство по планированию

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19 Planning your deployment
General deployment considerations
For information on using LDAP SyncService, see the Symantec Mail Security for
SMTP Administration Guide .
Load balancing
Symantec Mail Security for SMTP is not intended to be used for load balancing.
Administrators can associate only one host name or IP address as the MTA to
which email is relayed. You must implement multiple Scanners to perform load
balancing.
Adjusting MX records
When you implement Symantec Mail Security for SMTP in front of a separate
MTA that receives inbound messages, you must to change the DNS mail
exchange (MX) records. The records must point incoming messages to the
system. Symantec Mail Security for SMTP should have a higher priority than
the existing MTA.
However, if you simply list Symantec Mail Security for SMTP as a higher-
weighted MX record in addition to the existing MX record, spammers can look
up the previous MTA’s MX record. This allows them to send spam directly to the
old server, bypassing your spam filtering. To prevent spammers from
circumventing the new spam-filtering servers, you should do one of the
following:
■
Remove the previous MTA’s MX record from DNS.
■
Block off the MTA from the Internet using a firewall.
■
Modify the firewall’s network address translation (NAT) tables to route
external IP addresses to internal non-routable IP addresses. You can then
map from the old server to Symantec Mail Security for SMTP.
■
When naming Symantec Mail Security for SMTP, ensure that the name you
choose does not imply its function. For example, antispam.yourdomain.com,
symantec.yourdomain.com, or antivirus.yourdomain.com are not good
choices.
Adjusting RAM and MySQL threads
The Control Center is a combination of Tomcat and MySQL applications. Tomcat
provides the Web-based interface, and MySQL is the database storage. Their
default configuration performs well in installations with a single Scanner and
low volume email traffic. In installations where multiple Scanners or large
amounts of spam are processed, increasing the amount of RAM allocated to