Another possible solution to this problem is to allow internal clients to speak directly to 10.0.0.2 and this would
completely avoid all the problems associated with address translation. However, this is not always practical.
7.4.2. Translation of Multiple IP Addresses (M:N)
A single SAT rule can be used to translate an entire range of IP addresses. In this case, the result is a
transposition where the first original IP address will be translated to the first IP address in the
translation list and so on.
For instance, a SAT policy specifying that connections to the 194.1.2.16/29 network should be
translated to 192.168.0.50 will result in transpositions which are described in the table below:
Original Address
Translated Address
194.1.2.16
192.168.0.50
194.1.2.17
192.168.0.51
194.1.2.18
192.168.0.52
194.1.2.19
192.168.0.53
194.1.2.20
192.168.0.54
194.1.2.21
192.168.0.55
194.1.2.22
192.168.0.56
194.1.2.23
192.168.0.57
In other words:
•
Attempts to communicate with 194.1.2.16 will result in a connection to 192.168.0.50.
•
Attempts to communicate with 194.1.2.22 will result in a connection to 192.168.0.56.
An example of when this is useful is when having several protected servers in a DMZ, and where
each server should be accessible using a unique public IP address.
Example 7.5. Translating Traffic to Multiple Protected Web Servers
In this example, we will create a SAT policy that will translate and allow connections from the Internet to five web
servers located in a DMZ. The NetDefend Firewall is connected to the Internet using the wan interface, and the
public IP addresses to use are in the range of 195.55.66.77 to 195.55.66.81. The web servers have IP addresses
in the range 10.10.10.5 to 10.10.10.9, and they are reachable through the dmz interface.
To accomplish the task, the following steps need to be performed:
•
Define an address object containing the public IP addresses.
•
Define another address object for the base of the web server IP addresses.
•
Publish the public IP addresses on the wan interface using the ARP publish mechanism.
•
Create a SAT rule that will perform the translation.
•
Create an Allow rule that will permit the incoming HTTP connections.
Command-Line Interface
Create an address object for the public IP addresses:
gw-world:/> add Address IP4Address wwwsrv_pub
Address=195.55.66.77-195.55.66.81
Now, create another object for the base of the web server IP addresses:
gw-world:/> add Address IP4Address wwwsrv_priv_base
7.4.2. Translation of Multiple IP
Addresses (M:N)
Chapter 7. Address Translation
354
Summary of Contents for DFL-1600 - Security Appliance
Page 27: ...1 3 NetDefendOS State Engine Packet Flow Chapter 1 NetDefendOS Overview 27 ...
Page 79: ...2 7 3 Restore to Factory Defaults Chapter 2 Management and Maintenance 79 ...
Page 146: ...3 9 DNS Chapter 3 Fundamentals 146 ...
Page 227: ...4 7 5 Advanced Settings for Transparent Mode Chapter 4 Routing 227 ...
Page 241: ...5 4 IP Pools Chapter 5 DHCP Services 241 ...
Page 339: ...6 7 Blacklisting Hosts and Networks Chapter 6 Security Mechanisms 339 ...
Page 360: ...7 4 7 SAT and FwdFast Rules Chapter 7 Address Translation 360 ...
Page 382: ...8 3 Customizing HTML Pages Chapter 8 User Authentication 382 ...
Page 386: ... The TLS ALG 9 1 5 The TLS Alternative for VPN Chapter 9 VPN 386 ...
Page 439: ...Figure 9 3 PPTP Client Usage 9 5 4 PPTP L2TP Clients Chapter 9 VPN 439 ...
Page 450: ...9 7 6 Specific Symptoms Chapter 9 VPN 450 ...
Page 488: ...10 4 6 Setting Up SLB_SAT Rules Chapter 10 Traffic Management 488 ...
Page 503: ...11 6 HA Advanced Settings Chapter 11 High Availability 503 ...
Page 510: ...12 3 5 Limitations Chapter 12 ZoneDefense 510 ...
Page 533: ...13 9 Miscellaneous Settings Chapter 13 Advanced Settings 533 ...
