Virtual data loopback and/or data capture in a computing system

A method for providing virtual data loopback in a computing system including a first instruction executing device, a second instruction executing device, and multiple interfaces for connecting the computing system with an external computing system, the method comprising:

• forwarding a data packet from the first instruction executing device to the second instruction executing device;
• the second instruction executing device identifying egress interface information from the data packet, the egress interface information indicating a first interface for forwarding the data packet out of the computing system;
• based on the identified egress interface information indicating the first interface, the second instruction executing device automatically determining a second interface corresponding to the first interface;
• the second instruction executing device inserting into the data packet ingress interface information that indicates the determined second interface;
• the second instruction executing device forwarding the data packet, including the ingress interface information, back to the first instruction executing device;
• and
• the first instruction executing device identifying from the data packet the ingress interface information that indicates the determined second interface;
• such that the data packet is looped back to the first instruction executing device without being communicated via the first or second interface, and such that from the perspective of the first instruction executing device the data packet was received via the second interface;
• wherein the first instruction executing device and the second instruction executing device each comprise at least one of a processor or a configurable logic device.