This counts configuration-loss events -- as categorized by the reason codes in cat2600TsPortCfgLossRC -- that occurred on this port after it had already completed its Token-Ring join process and then lost communication with the ring. An admin watches this counter to spot a port that keeps dropping off the ring after initially joining successfully, distinct from a port that simply never joins at all. A steadily climbing count here on one ring port, even though the port shows link up, points to intermittent ring instability worth investigating with cat2600TsPortCfgLossRC.