This identifies the specific node in the Cascade multi-switch mesh at which the circuit establishment attempt actually failed, complementing cktFailReason by telling the admin where in the path the problem occurred, not just what kind of problem it was. For example, if multiple circuits destined for different endpoints all report the same cktFailNode value, that node itself -- rather than any individual circuit's configuration -- is likely the common point of failure, such as a switch out of VC buffer resources.