Firewall
Configuring NAT Rules to Securely Access a Remote Network
Cisco ISA500 Series Integrated Security Appliances Administration Guide
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6
Configuring Static NAT Rules
Static NAT creates a fixed translation of a real address to a mapped address.
Because the mapped address is the same for each consecutive connection, static
NAT allows bidirectional connection initiation, both to and from the host (if a
firewall rule allows it). With dynamic PAT, on the other hand, each host uses a
different address or port for each subsequent translation, so bidirectional initiation
is not supported.
Up to 64 static NAT rules can be configured on the security appliance. You must
create firewall rules to allow access so that the static NAT rules can function
properly.
NOTE
If you wish to enable Remote Management of the security appliance, do not create
a static NAT rule that maps an internal server to the WAN IP address. For example,
if you create a static NAT rule that maps 192.168.75.100 to the WAN IP address,
173.39.202.68, remote users will not have access to the configuration utility via
http://173.39.202.68:8080.
STEP 1
Click
Firewall > NAT > Static NAT
.
STEP 2
To add a static NAT rule, click
Add
.
Other options:
To edit an entry, click the
Edit
(pencil) icon. To delete an entry, click
the
Delete
(x) icon. To delete multiple entries, check them and click
Delete
.
The Static NAT Rule - Add/Edit
window opens.
STEP 3
Enter the following information:
•
WAN:
Choose either WAN1 or WAN2 as the WAN port.
•
Public IP:
Choose an IP address object as the public IP address.
•
Private IP:
Choose an IP address object as the private IP address.
If the IP address that you want is not in the list, choose
Create a new
address
to create a new IP address object. To maintain the IP address
objects, go to the
Networking > Address Management
page. See
.
NOTE:
Firewall rules must be configured to allow access. You can go to the
Firewall > Access Control > ACL Rules
page or click the
Create Rule
link
to do this, but save your settings on this page first.
STEP 4
Click
OK
to save your settings.