Method for managing hard disk drive expanders in a cluster storage system

Abstract

A method for managing HDD expanders in a cluster storage system is provided. The method according to one embodiment is implemented by each HDD expander connected indirectly to a host computer, and includes: indicating a device type not of HDD expander to the host computer when a device-type request originates from the host computer; and indicating a device type of HDD expander to a node that initiates the device-type request when otherwise.

1 - 13 . (canceled) 
     
     
         14 . A method for managing hard disk drive (HDD) expanders in a cluster storage system, the cluster storage system further including a host computer connected to the HDD expanders to form a hierarchical tree structure, the method comprising steps, to be implemented by each of those of the HDD expanders that is connected indirectly to the host computer, of:
 upon receiving a device-type request for inquiring a device type from a parent node of the HDD expander in the hierarchical tree structure, determining whether the device-type request originates from the host computer;   when it is determined that the device-type request originates from the host computer, transmitting a device-type reply indicating a device type not of HDD expander to the host computer; and   when it is determined that the device-type request does not originate from the host computer, transmitting a device-type reply indicating a device type of HDD expander to a node that initiates the device-type request, and forwarding the device-type request to each child node of the HDD expander in the hierarchical tree structure.   
     
     
         15 . The method of  claim 14 , further comprising steps, to be implemented by one of the HDD expanders that is connected directly to the host computer, of:
 upon receiving a device-type request for inquiring a device type from the host computer, transmitting a device-type reply indicating a device type of HDD expander to the host computer, and forwarding the device-type request to each child node of said one of the HDD expanders in the hierarchical tree structure.   
     
     
         16 . The method of  claim 15 , the cluster storage system further including a plurality of HDD connected to the HDD expanders, the method further comprising steps, to be implemented by said one of the HDD expanders that is connected directly to the host computer, of:
 upon receiving an access request for accessing hard disk drives from the host computer, transmitting the access request to each descendant node of said one of the HDD expanders in the hierarchical tree structure;   
       after having received from every single working descendant node of said one of the HDD expanders in the hierarchical tree structure, a report indicating a unique address of each HDD that is connected directly to the working descendant node, generating an access reply including a unique address of each HDD that is connected directly to said one of the HDD expanders, and the unique address of said each HDD that is connected directly to to said every single working descendant node; and
 transmitting the access reply to the host computer. 
 
     
     
         17 . The method of  claim 16 , wherein, the report indicating a relationship of the unique address of the child node, with the unique address of said one of the HDDs that is connected directly to the child node. 
     
     
         18 . The method of  claim 14 , wherein, the device-type request including a unique address of the node that originates the device-type request. 
     
     
         19 . A cluster storage system comprising:
 a host computer; and   a plurality of hard disk drive (HDD) expanders connected to said host computer to form a hierarchical tree structure,   wherein those of said HDD expanders that are connected indirectly to said host computer are each configured to:
 upon receiving a device-type request for inquiring a device type from a parent node of said HDD expander in the hierarchical tree structure, determine whether the device-type request originates from said host computer, 
 when it is determined that the device-type request originates from said host computer, transmit a device-type reply indicating a device type not of HDD expander to said host computer, and 
 when it is determined that the device-type request does not originate from said host computer, transmit a device-type reply indicating a device type of HDD expander to a node that initiates the device-type request, and forward the device-type request to each child node of said HDD expander in the hierarchical tree structure.