McAfee SG310, Руководство администратора

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McAfee UTM Firewall 4.0.4 Administration Guide 177
Firewall menu options
NAT
The entries in the Translate packet fields pane describe how matching packets should be altered:
12
Enter the address to replace the Destination Address in the To Destination Address field. The To
Destination Address is typically the private address of a host on the LAN.
13
Enter the translated port of the packet in the Optional To Ports field. Normally, this field is set to the
port of a service on your internal server. Leave this blank if you want the port to remain unchanged. You
can also enter the port on the host at To Destination Address to service the request.
Note: Ports cannot be translated for IP protocols or ICMP messages. Also, since a predefined service may
contain multiple protocols, the port cannot be translated if the Services field is set to a predefined service.
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Click Finish. The rule is added to the Port Forwarding rule objects page. If you cleared the Create Packet
Filter Rule checkbox, you must create a packet filtering rule that corresponds with the port forwarding
rule. See
Creating a packet filter rule .
Editing a port forwarding rule
1
From the Firewall menu, click NAT. The Port Forwarding page appears.
2
Click the edit icon for the port forward rule you want to edit. The Modify Port Forward page appears.
3
Make your changes and click Finish.
Disabling a port forwarding rule
Use this procedure to temporarily disable a rule.
Tip: Click the enable/disable checkbox to the left of the object list to quickly disable the rule. The page refreshes,
and the check mark is no longer displayed, indicating the rule is disabled.
1
From the Firewall menu, click NAT. The Port Forwarding page appears.
2
Clear the Enable checkbox.
3
Click Finish.
Enabling a port forwarding rule
Use this procedure to re-enable a disabled rule.
Tip: Click the enable checkbox to the left of the object list to quickly re-enable the rule. The page refreshes, and
a check mark indicates the rule is enabled again.
1
From the Firewall menu, click NAT. The Port Forwarding page appears.
2
Click the edit icon for the port forward rule you want to edit. The Modify Port Forward page appears.
3
Select the Enable checkbox.
4
Click Finish.
Deleting a port forwarding rule
1
From the Firewall menu, click NAT. The Port Forwarding page appears.
2
Click the delete icon for the port forward rule you want to delete. You are prompted to confirm the delete.
3
Click OK.
Example: Basic port forwarding rule to an internal mail server
The following is an example of using port forwarding to allow mail servers on the Internet to send email via
SMTP to a mail server on your DMZ or LAN.
Caution: Precautions must be taken when configuring the mail server, otherwise you could become susceptible to
such abuse as unauthorized relaying of unsolicited email (spam) using your server. Configuration of the email
server is outside the scope of this manual.