Network Tracing for Data Centers

A network device comprising:

• an input buffer operable to receive a packet from a source device;
• an output buffer operable to hold an outgoing packet to a destination device;
• tracing logic connected to the input buffer and the output buffer, the tracing logic configured to:
• determine multiple paths along which a packet may travel from the network device to the destination device;
• despite routing information in the network device specifying a particular path for the packet to the destination device, determine a selection of paths from among the multiple paths for tracing;
• and
• send an outgoing network tracing packet down each path of the selection of paths.

A device comprising:

• a packet buffer in a network device, the packet buffer comprising a network packet received from a source network device and destined for a destination network device;
• tracing logic connected to the packet buffer, the tracing logic configured to:
• obtain tracing execution criteria;
• evaluate the tracing execution criteria to determine whether to execute network tracing toward the destination network device;
• when network tracing will proceed with respect to the destination network device for the network packet:
• determine selected network paths to trace from among multiple network paths supported by the network device toward the destination network;
• and
• sending an outgoing network tracing packet down each selected network path.