Storage system and file arrangement method of storage system

1. A storage system which is coupled to a host and which performs an operation with respect to a stored file based on a file operation request from the host, the storage system comprising:

a controller; and a plurality of storage devices of which reliability and security levels differ from one another, wherein

the controller determines a reliability requirement and a security requirement of the stored file based on at least one of a type and a content of the stored file, determines a storage device from among the plurality of storage devices in which to store the stored file based on the determined reliability requirement and the determined security requirement, and stores the stored file in the determined storage device,

wherein

the controller manages the plurality of storage devices as a first volume in which the stored file is to be stored and a second volume in which a backup of the stored file is to be stored,

the second volume is constituted of a plurality of physical storage devices with different performances, the controller manages the second volume by classifying the physical storage devices into a plurality of storage tiers according to performances of the physical storage devices, and

the controller further determines the storage tier in which a backup file being a backup of the stored file is to be stored based on the determined reliability requirement and the security requirement of the stored file and stores the backup wherein

the storage system has a memory,

the memory stores information that identifies the stored file, information that identifies the host having issued the file operation request with respect to the stored file, and an access history table having a time point at which update processing of the stored file had been performed, and

the controller refers to the access history table to identify the stored file that is presumed not to be infected with the malware and performs rearrangement of the storage tier with respect to the identified stored file.

2. The storage system according to claim 1 , wherein

the controller performs rearrangement of the storage tier in which the backup file is stored in consideration of a time point of occurrence of a logical failure of the host which is triggered by a detection of a failure of an application and/or a system of the host.

3. The storage system according to claim 2 , wherein

the controller performs rearrangement of the storage tier in which the backup file is stored in consideration of an infection time point of the host which is triggered by a detection of a malware infection of the host.

4. The storage system according to claim 3 , wherein

the storage system is coupled to a plurality of the hosts, and

the controller performs rearrangement of the storage tier in which the backup file is stored based on information that identifies the host having been infected with the malware and the infection time point of the host having been infected with the malware.

5. The storage system according to claim 1 , wherein

the controller rearranges the identified stored file to the storage tier on a higher level than the storage tier in which the identified stored file is currently arranged.

6. The storage system according to claim 5 , wherein

the controller rearranges the identified stored file to the storage tier on an uppermost level.

7. The storage system according to claim 1 , wherein

the controller rearranges the identified stored file to the storage tier of the storage device with higher reliability and a higher security level than the storage device in which the identified stored file is currently arranged.

8. The storage system according to claim 1 , wherein

the memory stores information that identifies the stored file, a time point at which update processing of the stored file had been performed, and a generation information management table having a file size of the stored file, and

the controller also refers to the generation information management table to identify the stored file that is presumed not to be infected with the malware and performs rearrangement of the storage tier with respect to the identified stored file.

9. A file arrangement method in a storage system which is coupled to a host and which performs an operation with respect to a stored file based on a file operation request from the host,

the storage system including: a controller; and a plurality of storage devices of which reliability and security levels differ from one another,

the file arrangement method comprising the steps of:

determining a reliability requirement and a security requirement of the stored file based on at least one of a type and a content of the stored file;

determining a storage device from among the plurality of storage devices in which to store the stored file based on the determined reliability requirement and the determined security requirement;

storing the stored file in the determined storage device,

managing the plurality of storage devices as a first volume in which the stored file is to be stored and a second volume in which a backup of the stored file is to be stored, wherein

the second volume is constituted of a plurality of physical storage devices with different performances;

managing the second volume by classifying the physical storage devices into a plurality of storage tiers according to performances of the physical storage devices, and

determining the storage tier in which a backup file being a backup of the stored file is to be stored based on the determined reliability requirement and the security requirement of the stored file and stores the backup, wherein

the storage system has a memory,

the memory stores information that identifies the stored file, information that identifies the host having issued the file operation request with respect to the stored file, and an access history table having a time point at which update processing of the stored file had been performed, and

the controller refers to the access history table to identify the stored file that is presumed not to be infected with the malware and performs rearrangement of the storage tier with respect to the identified stored file.