Storage control system and control method for storage control which suppress the amount of power consumed by the storage control system

Abstract

One or more master CHN 21 AM and one or more back-up CHN 21 AC are provided. In each of the one or more back-up CHNs 21 AC, the I/O processor 504 is in a power on state, and the NAS processor is in a power off state. The I/O processor 504 accesses a shared memory 25 periodically, and if the fact that a problem has occurred in any master CHN 21 AM has been written to the shared memory 25 , then the power supply of the NAS processor 506 is turned on, and processing is carried out for switching the back-up CHN 21 AC in which the I/O processor 504 is installed, to a master CHN 21 AM.

1 . (canceled)  
     
     
         2 . A storage control system for controlling the storage of data in storage devices, comprising: 
 a plurality of storage devices for storing data;    a storage device control section for controlling storing of data in said plurality of storage devices; and    a plurality of channel control sections coupled to a local area network external to said storage control system,    wherein said plurality of channel control sections includes one or more first channel control sections and one or more second control sections, and    wherein one of said one or more first channel control sections and said one or more second channel control sections communicate with each other indicating that a problem has occurred in said one first channel control section.    
     
     
         3 . The storage control system according to  claim 2 , wherein said one first channel control section writes problem occurrence information indicating that said problem has occurred, and 
 wherein any one of said one or more second channel control sections, if detecting said problem occurrence information, carries out exclusion processing for prohibiting a further one of said one or more second channel control sections from switching to said one first channel control section, and executes switching processing for switching said one of said one or more second channel control sections to another one of said one or more first channel control sections.    
     
     
         4 . The storage control system according to  claim 2 , wherein one of said one or more first channel control sections sets a power saving state, if said problem has occurred, and 
 wherein one of said one or more second channel control sections releases the power saving state, if detecting that said problem has occurred in said one first channel control section.    
     
     
         5 . The storage control system according to  claim 2 , wherein category information indicating whether a channel control section is a first or a second channel control section is registered for each of said plurality of channel control sections, and 
 wherein said first channel control section or said second channel control section changes the category information corresponding to said first channel control section, to information indicating that the corresponding channel control section is a second channel control section, if said problem has occurred.    
     
     
         6 . The storage control system according to  claim 2 , wherein two or more logical units, which are logical devices for storing data, are provided in said plurality of storage devices; 
 wherein corresponding logical unit information indicating which logical unit is used by a channel control section, of said two or more logical units, is registered, and    wherein said first channel control section or said second channel control section erases the first corresponding logical unit information corresponding to said first channel control section, if said problem has occurred, and associates said first corresponding logical unit information with said second channel control section.    
     
     
         7 . The storage control system according to  claim 2 , wherein correspondence data indicating correspondence relationships between said one or more first channel control sections and said one or more second channel control sections is stored, 
 wherein said one or more first channel control sections and said one or more second channel control sections being associated, in said correspondence data, in at least one of the following states, (A)-(D):    (A) the number of second channel control sections corresponding to one of said one or more first channel control sections is one, and the number of first channel control sections corresponding to one of said one or more second channel control sections is also one,    (B) the number of said second channel control sections corresponding to one of said one or more first channel control sections is two or more, but the number of said first channel control sections corresponding to one of said one or more second channel control sections is one,    (C) the number of said first channel control sections corresponding to one of said one or more second channel control sections is two or more, but the number of said second channel control sections corresponding to one of said one or more first channel control sections is one, and    (D) the number of said second channel control sections corresponding to one of said one or more first channel control sections is two or more, and the number of said first channel control sections corresponding to one of said one or more second channel control sections is also two or more; and    wherein said second channel control section refers to said correspondence data, and if a problem has occurred in a first channel control section releases the power saving state in said second channel control section.    
     
     
         8 . The storage control system according to  claim 2 , wherein said plurality of channel control sections include one or more third channel control sections, 
 wherein said one or more second channel control sections and said third channel control section assuming a standby state in such a manner that they can operate a first channel control section, in the place of said first channel control section in which said problem has occurred, but said third channel control section assuming a normal state, unlike said second channel control section; and    if said problem has occurred in said first channel control section, then said third channel control section becomes said first channel control section, by means of said third channel control section operating in a normal state, and the power saving state of said second channel control section is released and said second channel control section becomes said third channel control section.    
     
     
         9 . The storage control system according to  claim 8 , wherein said first channel control section writes problem occurrence information indicating that said problem has occurred, and 
 wherein if said second channel control section, has detected said problem occurrence information prior to said third channel control section, then said second channel control section ignores said problem occurrence information.    
     
     
         10 . The storage control system according to  claim 8 , wherein if a separate channel control section to a first channel control section in which said problem has occurred is installed in said storage control system, then said separate channel control section is started up as said second channel control section.  
     
     
         11 . A control method for a storage control system for controlling storing data in storage devices, wherein said storage control system comprises a plurality of channel control sections connected to a local area network that is external to said storage control system, wherein said plurality of channel control sections includes one or more first channel control sections which is in a normal state, and one or more second channel control sections which assume a standby state in which they can operate as said first channel control sections, said control method comprising the steps of: 
 if a problem has occurred in said first channel control section, recording, by said first channel control section, the fact that said problem has occurred;    detecting, by said second channel control section, the fact that said problem has occurred in said first channel control section; and    releasing, by said second channel control section, said power saving state, if it has been detected that said problem has occurred.    
     
     
         12 . The control method according to  claim 11 , further comprising the steps of: 
 writing, by said first channel control section, problem occurrence information indicating that said problem has occurred; and    carrying out, by any one of a plurality of said second channel control sections, if detecting said problem occurrence information, exclusion processing for prohibiting a further second channel control section from switching to said first channel control section, and executes switching processing for switching said one second channel control section to said first channel control section.    
     
     
         13 . The control method according to  claim 11 , further comprising the steps of: 
 setting, by said first channel control section, said first processor to a power saving state, if said problem has occurred; and    releasing, by said second channel control section, the power saving state, if detecting that said problem has occurred in said first channel control section.    
     
     
         14 . The control method according to  claim 11 , further comprising the steps of: 
 registering category information indicating whether a channel control section is a first or a second channel control section for each of said plurality of channel control sections; and    changing said first channel control section or second channel control section, the category information corresponding to said first channel control section, to information indicating that the corresponding channel control section is a second channel control section, if said problem has occurred.    
     
     
         15 . The control method according to  claim 11 , wherein two or more logical units, which are logical devices for storing data, are provided in said plurality of storage devices, 
 wherein corresponding logical unit information indicating which logical unit is used by a channel control, of said two or more logical units, is registered in said shared memory for each of said plurality of channel control sections, and    wherein said control method comprises a step whereby said first channel control section or second channel control section erases the first corresponding logical unit information corresponding to said first channel control section, if said problem has occurred, and associates said first corresponding logical unit information with said second channel control section.    
     
     
         16 . The control method according to  claim 11 , wherein correspondence data indicating correspondence relationships between said first channel control sections and said second channel control sections is stored, 
 wherein said first channel control sections and said second channel control sections being associated, in said correspondence data, in at least one of the following states, (A)-(D):    (A) the number of said second channel control sections corresponding to one of said first channel control sections is one, and the number of said first channel control sections corresponding to one of said second channel control sections is one,    (B) the number of said second channel control sections corresponding to one of said first channel control sections is two or more, but the number of said first channel control sections corresponding to one of said second channel control sections is one,    (C) the number of said first channel control sections corresponding to one of said second channel control sections is two or more, but the number of said second channel control sections corresponding to one of said first channel control sections is one, and    (D) the number of said second channel control sections corresponding to one of said first channel control sections is two or more, and the number of said first channel control sections corresponding to one of said second channel control sections is also two or more; and    wherein said control method comprises a step whereby said second channel control section refers to said correspondence data, and if a problem has occurred in a first channel control section corresponding to the second channel control section, then releases the power saving state in said second channel control section.    
     
     
         17 . The control method according to  claim 11 , wherein said plurality of channel control sections include one or more third channel control sections, which assume a standby state in such a manner than they can operate as said first channel control sections; and 
 said control method further comprises the steps of:    detecting, by said third channel control section, the fact that said problem has occurred in said first channel control section;    acquiring, by said third channel control section, information used by said first channel control section, and causing said third channel control section to operate as a first channel control section; and    releasing, by said second channel control section, said power saving state, when said third channel control section operates as said first channel control section.    
     
     
         18 . The control method according to  claim 17 , further comprising the step of: 
 writing, by said first channel control section, problem occurrence information indicating that said problem has occurred,    wherein if said second channel control section has detected said problem occurrence information prior to said third channel control section, then said second channel control section ignores said problem occurrence information.    
     
     
         19 . The control method according to  claim 17 , further comprising a step of: 
 if a separate channel control section to a first channel control section in which said problem has occurred is installed in said storage control system, then starting up said separate channel control section as said second channel control section.