Automatic isolation in loops
View Patent ↗A loop network hub port with an automatic bypass feature. The automatic bypass feature causes the hub port to enter a bypass mode upon detection of a specified loop failure initialization sequence from a node port attached to the hub port. The hub port does not propagate loop failure initialization data generated by the attached node port upon the failure of a data channel from the hub port to the node port. The hub port replaces loop failure initialization data received from the node port with buffer data and conceals the node port failure from the remainder of the loop. Upon detection of the loop failure initialization sequence received from the attached node port, the hub port enters a bypass mode and maintains that bypass mode until a recovery sequence is received from the node port. At that point, the hub port reinserts the node port into the loop.
1. A fiber channel system, comprising:
a loop comprising a plurality of connected hub ports arranged in a loop, each hub port connected to another hub port, and a plurality of node ports, each node port connected to a corresponding hub port but separated from the loop, each node port for sending failure initialization data in the form of Loop Initialization Primitive (LIP) F 8 ordered sets back to its corresponding hub port upon detecting a failure in data being received by the node port, said hub ports each including an error detecting portion which detects LIP F 8 ordered sets received from its corresponding node port, and a switch electrically controlled to pass information from said loop through a node port when said node port is operating properly, and to control said switch to bypass said node port when said node port is sending LIP F 8 ordered sets indicative of errors.