D-Link D DFL-500 DFL-500, Руководство пользователя

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DFL-500 User Manual
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create an external address for the web server on the Internet. You must then add a virtual IP to the firewall
that maps the external IP address of the web server to the actual address of the web server on your internal
network. To allow connections from the Internet to the web server, you must then add an Ext
-> Int firewall
policy and set Destination to the virtual IP.
You can create two types of virtual IPs:
Static NAT
Used in Ext -> Int policies to translate an address on the Internet to a hidden address on the internal
network. Static NAT translates the source address of outbound packets to the address to the
address on the Internet.
Port
Forwarding
Used in Ext -> Int policies to translate an address and a port number on a less secure network to a
hidden address and, optionally, a different port number on a more secure network. Using port
forwarding you can also route packets with a specific port number and a destination address that
matches the IP address of the interface that receives the packets. This technique is called port
forwarding or port address translation (PAT). You can also use port forwarding to change the
destination port of the forwarded packets.
If you use the setup wizard to configure internal server settings, the firewall adds port forwarding virtual
IPs and Ext
-> Int policies for each server that you configure.
Virtual IPs are not required in Transparent mode.
This section describes:
•
Adding static NAT virtual IPs
•
Using port forwarding virtual IPs
•
Adding policies with virtual IPs
Adding static NAT virtual IPs
•
Go to Firewall > Virtual IP .
•
Select New to add a virtual IP.
•
Enter a Name for the virtual IP.
The name can contain numbers (0-9), uppercase and lowercase letters (A-Z, a-z), and the special
characters - and _. Other special characters and spaces are not allowed.
•
Make sure Type is set to Static NAT.
•
In the External IP Address field, enter the external IP address to be mapped to an address on the
internal network.
For example, if the virtual IP provides access from the Internet to a web server on your internal
network, the external IP address must be a static IP address obtained from your ISP for your web
server. This address must be a unique address that is not used by another host and cannot be the
same as the IP address of the firewall external interface. However, this address must be routed to the
firewall external interface.