Method and apparatus for improving performance of a loop network

A loop network for conducting communications among a plurality of dual-ported devices connected to a plurality of loops, with each port connected to a different loop, the loop network comprising:

• means for selectively bypassing redundant ports on the plurality of loops by a first command means;
• means for bypassing the port of a device by a second command means in response to a fault;
• means for enabling all the bypassed redundant ports with a single Loop Port Enable All (LPEall) Fibre Channel Arbitrated Loop command to all ports using the first command means without enabling the port bypassed in response to the fault, wherein the loop network has at least one enclosure with an enclosure services device, the loop network is a Fibre Channel Arbitrated Loop (FC-AL), and the first command means is configured to provide a Fibre Channel Arbitrated Loop command;
• and
• selectively bypassing redundant ports on the loops with port accesses balanced across the loops by alternating bypassing first loop ports on every other device and second loop ports on remaining devices.

An enclosure for inclusion within a loop network comprising a plurality of loops, the enclosure comprising:

• a plurality of devices comprising a plurality of ports, each port configured to connect to a different loop of the plurality of loops;
• means for selectively bypassing each port of the plurality of devices;
• means for bypassing a port of a device of the plurality of devices in response to a fault;
• means for enabling the selectively bypassed ports with a single Loop Port Enable All (LPEall) Fibre Channel Arbitrated Loop command to all ports without enabling the port bypassed in response to the fault, wherein the plurality of ports are configured to connect to Fibre Channel Arbitrated Loops (FC-AL) and the means for selectively bypassing each port is configured to respond to a Fibre Channel Arbitrated Loop command;
• and
• means for selectively bypassing redundant ports on the loops with port accesses balanced across the loops by alternating bypassing first loop ports on every other device and second loop ports on remaining devices.

An apparatus for bypassing a port within an enclosure the apparatus comprising:

• a bypass circuit configured to receive a port bypass control signal and bypass a port in response to assertion of the port bypass control signal;
• a bypass control module configured to provide the bypass control signal;
• the bypass control module further configured to assert the bypass control signal in response to a Fibre Channel Arbitrated Loop command;
• the bypass control module further configured to assert the bypass control signal in response to faults communicated by a storage enclosure services device;
• the bypass control module further configured to de-assert the bypass control signal in response to a single Loop Port Enable All (LPEall) Fibre Channel Arbitrated Loop command if the bypass control signal is not asserted in response to faults communicated by the storage enclosure services device;
• and
• selectively bypassing redundant ports with port accesses balanced across two loops by alternating bypassing first loop ports on every other device and second loop ports on remaining devices.

A system for improving communications among a plurality of multi-ported devices connected to a plurality of loops, with each port connected to a different loop, the system comprising:

• means for bypassing selected ports in response to a Fibre Channel Arbitrated Loop command;
• means for bypassing a port in response to a fault;
• means for enabling the selected ports in response to a single Loop Port Enable All (LPEall) Fibre Channel Arbitrated Loop command without enabling the port bypassed in response to the fault;
• and
• means for selectively bypassing redundant ports on the loops with port accesses balanced across the loops by alternating bypassing first loop ports on every other device and second loop ports on remaining devices.

A computer readable storage medium with a computer program product which comprising computer readable program code means for improving performance in a loop network, the loop network having a first loop, a second loop and a plurality of dual-ported devices each with one port on each loop, the program code means performing the steps of:

• selectively bypassing redundant ports on the plurality of loops by a first command means;
• bypassing the port of a device by a second command means in response to a fault;
• and
• enabling all the bypassed redundant ports with a single Loop Port Enable All (LPEall) Fibre Channel Arbitrated Loop command to all ports using the first command means without enabling the port bypassed in response to a fault, wherein the first command means does not enable the port bypassed in response to the fault and the second command means is the enclosure services device;
• and
• selectively bypassing redundant ports on the loops with port accesses balanced across the loops by alternating bypassing first loop ports on every other device and second loop ports on remaining devices.