Virtual IPs

Static Virtual IPs (VIP) are used to map external IP addresses to internal IP addresses. This is also called destination NAT, where a packet's destination is being NAT'd, or mapped, to a different address.

Static VIPs are commonly used to map public IP addresses to resources behind the FortiProxy unit that use private IP addresses. A static on-to-one VIP is when the entire port range is mapped. A port forwarding VIP is when the mapping is configured on a specific port or port range. See Virtual IPs with port forwarding for more information.

VIPs are considered local IP addresses if responding to ARP requests on these external IP addresses is enabled (set arp-reply enable, by default). In this case, the FortiProxy is considered a destination for those IP addresses and can receive reply traffic at the application layer successfully. However, as a side-effect, once a VIP has been configured, even if it is never used in a policy, the FortiProxy considers it as a local address and will not forward traffic based on the routing table. Therefore, any unused VIPs should be deleted to prevent any unexpected behavior.

Sample configuration

To view the virtual IPs, go to Policy & Objects > Virtual IPs.

Hover over the leftmost edge of the column heading to display the Configure Table icon, which you can use to select the columns to display or to reset all the columns to their default settings. You can also drag column headings to change their order.

The following options are available:

Create New > Virtual IP	Add a new virtual IP. See Create or edit a virtual IP.
Create New > Virtual IP Group	Add a new virtual IP group. See Create or edit a virtual IP group.
Edit	Edit the selected virtual IP or virtual IP group. See Create or edit a virtual IP or Create or edit a virtual IP group
Delete	Remove the selected virtual IP or virtual IP group.
Search	Search for text in any column.
Name	The name of the virtual IP or virtual IP group.
Interfaces	The domain name.
Details	The interface to which the virtual IP or virtual IP group is bound.
Comments	Optional description of the virtual IP or virtual IP group.
Ref.	Displays the number of times the object is referenced to other objects. To view the location of the referenced object, select the number in Ref., and the Object Usage window appears displaying the various locations of the referenced object.
extip	External IP address or range for the virtual IP.