Virtual Private Cloud OnDemand Networking Guide

7 Depending on which type of NAT rule you want to create, click one of the following options:
Option Description
SNAT
A source NAT rule changes the source IP address and, optionally, port of
outgoing packets. When you create an SNAT rule in
Virtual Private Cloud OnDemand, by default the port and protocol are set
to “any.” To change the default port and protocol settings for an SNAT
rule, edit the settings in vCloud Director.
DNAT
A destination NAT rule changes the destination IP address and, optionally,
port of inbound packets.
Depending on which option you chose, the dialog refreshes with the required fields.
8 Depending on which type of NAT rule you are creating, complete the following settings:
Source NAT (SNAT) (inside -> outside)
Option Description
Original (Internal) Source
Enter the original IP address or range of IP addresses to apply to this rule.
The original addresses are the IP addresses of the virtual machine (or
machines) for which you are configuring SNAT so that they can send
traffic to the external network.
Translated (External) Source
Specifies the IP address to which source addresses (the virtual machines)
on outbound packets are translated to when they send traffic to the
external network.
The translated address is always the public IP address of the gateway for
which you are configuring the SNAT rule.
Select the required IP address from the drop-down menu.
Destination NAT (DNAT) (outside -> inside)
Option Description
Original (External) IP
Specifies the destination IP address to which the rule applies; the address
is always the public IP address of the gateway for which you are
configuring the DNAT rule.
Select the required IP address from the drop-down menu.
Protocol
Select the protocol to which the rule applies—any, TCP, UDP, TCP/UDP,
and ICMP. By default, the protocol is set to “any.”
Original Port/Range
(Optional) Enter the port or port range that the incoming traffic uses on the
gateway to connect to the internal network on which the virtual machines
are connected.
ICMP type
If you selected ICMP (an error reporting and diagnostic utility used
between devices to communicate error information) in the Protocol field,
select the ICMP type from the drop-down menu. ICMP messages are
identified by the “type” field. By default, the ICMP type is set to “any.”
Translated (Internal) IP/Range
Enter the IP address or a range of IP addresses to which destination
addresses on inbound packets will be translated.
The translated addresses are the IP addresses of the virtual machine (or
machines) for which you are configuring DNAT so that they can receive
traffic from the external network.
Translated Port/Range
(Optional) Enter the port or port range that traffic connects to on the
virtual machines on the isolated network.
9 Select Enable this rule and click Save.
The NAT Rules dialog appears.
10 Click Add to add additional rules or click Finish to commit the rules to the gateway.
vCloud Air - Virtual Private Cloud OnDemand Networking Guide
24 VMware, Inc.