Network path detection and monitoring

A computing device comprising:

• one or more processors;
• and
• one or more non-transitory computer-readable media storing computer-executable instructions that, when executed by the one or more processors, cause the one or more processors to:
• provision multiple nodes of a network to conduct a path tracing session using probe packets, the multiple nodes including a source node, a midpoint node, and a sink node, provisioning the multiple nodes including:
• causing the source node to generate an individual probe packet to traverse an equal-cost multi-path (ECMP) path through the network, the individual probe packet having a path tracing indicator (PTI) and an entropy value, the PTI corresponding to the ECMP path, the ECMP path including the midpoint node,
• causing the midpoint node to record path tracing information in the individual probe packet, and
• causing the sink node to forward the individual probe packet to a controller in response to the PTI after the individual probe packet has traversed the ECMP path;
• analyzing the path tracing information in the individual probe packet to produce a mapping of the entropy value to the ECMP path;
• and
• using the mapping to cause the source node to generate a subsequent probe packet to traverse the ECMP path through the network.

A method comprising:

• causing a source node to generate a first probe packet to traverse a multi-protocol label switching (MPLS) network, the first probe packet including a first entropy value;
• causing one or more midpoint nodes of the MPLS network to record path tracing information in the first probe packet responsive to a path tracing indicator (PTI) of the first probe packet;
• receiving the first probe packet from a sink node after the first probe packet has traversed the MPLS network via at least one of the midpoint nodes;
• analyzing the path tracing information to discover an equal-cost multi-path (ECMP) path that the first probe packet traversed across the MPLS network;
• producing a first entropy-to-path mapping of the first entropy value to the ECMP path;
• and
• using the first entropy-to-path mapping to monitor the ECMP path by causing the source node to produce a subsequent probe packet that includes the first entropy value.