Method to facilitate fast context switching for partial and extended path extension to remote expanders

摘要

A method, apparatus, and system for switching from an existing target end device to a next target end device in a multi-expander storage topology by using Fast Context Switching. The method enhances Fast Context Switching by allowing Fast Context Switching to reuse or extend part of an existing connection path to an end device directly attached to a remote expander. The method can include reusing or extending at least a partial path of an established connection between an initiator and the existing target end device for a connection between the initiator and the next target end device, whereby the existing target end device and the next target end device are locally attached to different expanders.

主权项

1. A method for switching from an existing target end device to a next target end device in a multi-expander storage topology, the multi-expander topology including at least one initiator and at least two expanders, the at least two expanders including a first expander and a second expander, wherein the first expander is locally attached to the existing target end device and the second expander is locally attached to the next target end device, the method comprising:
receiving, from an initiator of the at least one initiator or an upstream expander of the at least two expanders, a done switch issued by the initiator, wherein the done switch is configured to close an established connection between the initiator and the existing target end device; receiving, from the initiator or the upstream expander, a switch address frame, wherein the switch address frame is configured to instruct the second expander locally attached to the next target end device to establish a connection between the initiator and the next target end device; and performing at least one action, the at least one action including: reusing a partial path of the established connection between the initiator and the existing target end device for the connection between the initiator and the next target end device, wherein the existing target end device and the next target end device are locally attached to different expanders; or extending a path of the established connection between the initiator and the existing target end device for the connection between the initiator and the next target end device, wherein the existing target end device and the next target end device are locally attached to different expanders.