Table 1. Feature History
NAT DIA Tracker for Cisco IOS XE SD-WAN Devices
Cisco IOS XE Release 17.3.1aCisco vManage Release 20.3.1
This feature allows you to configure a system tracker to probe the transport interface periodically to determine if the Internet
or external network becomes unavailable.
The DIA tracker helps determine if the Internet or external network becomes unavailable. This feature is useful when NAT is
enabled on a transport interface in VPN 0 to allow data traffic from the router to exit directly to the Internet.
Refer to NAT DIA feature for NAT DIA configuration information.
If the Internet or external network becomes unavailable, the router continues to forward traffic based on the NAT route in
the service VPN. Traffic that is forwarded to the Internet gets dropped. To prevent the Internet-bound traffic from being
dropped, configure the DIA tracker on the edge router to track the status of the transport interface. The tracker periodically
probes the interface to determine the status of the Internet and return the data to the attach points that are associated
with the tracker.
When the tracker is configured on the transport interface, the interface IP address is used as source IP address for probe
IP SLA monitors the status of probes and measures the round trip time of these probe packets and compares the values with
the configured latency in the probe. When the latency exceeds the configured threshold value, the tracker considers the network
If the tracker determines that the local Internet is unavailable, the router withdraws the NAT route from Service VPN, and
reroutes the traffic based on the local routing configuration to overlay.
The local router continues to periodically check the status of the path to the interface. When it detects that the path is
functioning again, the router reinstalls the NAT route to the Internet.
Workflow for DIA NAT Tracker
Configure an interface tracker using Cisco System template. See Configure Interface Trackers.
Apply the tracker to a transport interface using either Cisco VPN Interface Ethernet or Cisco VPN Interface Cellular templates.