SNAT stands for Source Network Address Translation, and different vendors have slight variations in the implementation of SNAT. A simple explanation of the EdgeADC SNAT would be as follows.
Under normal circumstances, inbound requests would be directed to the VIP that would see the source IP of the request. So, for example, if a browser endpoint had an IP address of 81.71.61.51, this would be visible to the VIP.
When SNAT is in force, the original source IP of the request will be hidden from the VIP, and instead, it will see the IP address as provided in the SNAT rule. Thus, SNAT can be used in Layer 4 and Layer 7 load balancing modes.
Field
Description
Source IP
The Source IP address is optional, and it can be either a network IP address (with /mask) or a plain IP address. The mask can be either a network mask or a plain number, specifying the number of 1’s at the left side of the network mask. Thus, a mask of /24 is equivalent to 255.255.255.0.
Destination IP
The Destination IP address is optional, and it can be either a network IP address (with /mask) or a plain IP address. The mask can be either a network mask or a plain number, specifying the number of 1’s at the left side of the network mask. Thus, a mask of /24 is equivalent to 255.255.255.0.
Source Port
The source port is optional, it can be a single number, in which case it specifies only that port, or it can include a colon, which specifies a range of ports. Examples: 80 or 5900:5905.
Destination Port
The destination port is optional, it can be a single number, in which case it specifies only that port, or it can include a colon, which specifies a range of ports. Examples: 80 or 5900:5905.
Protocol
You can choose whether to use SNAT on a single protocol or all the protocols. We suggest being specific to be more precise.
SNAT to IP
SNAT to IP is a mandatory IP address or a range of IP addresses. Examples: 10.0.0.1 or 10.0.0.1-10.0.0.3.
SNAT to Port
The SNAT to Port is optional, it can be a single number, in which case it specifies only that port, or it can include a dash, which specifies a range of ports. Examples: 80 or 5900-5905.
Notes
Use this to put a friendly name to remind yourself why the rules exist. This is also useful for debugging in the Syslog.
