Computer system preventing storage of duplicate files

A storage control method effected via a computer system which includes:

• a computer;
• and
• a first storage system having one or more first logical storage devices where a plurality of files are stored,
• a second storage system having one or more second logical storage devices,
• wherein said storage control method comprising:
• said computer effecting operations of:
• calculating a plurality of hash values that are values intrinsic to contents of a plurality of files, respectively;
• and
• transmitting a plurality of hash values corresponding respectively to said plurality of files to said first storage system, and
• said first storage system effecting operations of:
• performing duplication determination by determining whether two or more identical hash values are contained in said plurality of hash values;
• and
• changing an access destination of a first file corresponding to a first hash value from among these two or more identical hash values, to a position having stored therein a second file corresponding to a second hash value from among these two or more identical hash values when there are said two or more identical hash values,
• migrating data stored in files stored in said one or more first logical storage devices to said one or more second logical storage devices, by not migrating first data of said first file to any of said one or more second logical storage devices, and migrating second data of said second file to any of said one or more second logical storage devices.

A non-transitory computer-readable medium embodying a storage control method effected via a computer system which includes:

• a computer;
• and
• a first storage system having one or more first logical storage devices where a plurality of files are stored,
• a second storage system having one or more second logical storage devices,
• wherein said storage control method comprising:
• said computer effecting operations of:
• calculating a plurality of hash values that are values intrinsic to contents of a plurality of files, respectively;
• and
• transmitting a plurality of hash values corresponding respectively to said plurality of files to said first storage system, and
• said first storage system effecting operations of:
• performing duplication determination by determining whether two or more identical hash values are contained in said plurality of hash values;
• and
• changing an access destination of a first file corresponding to a first hash value from among these two or more identical hash values, to a position having stored therein a second file corresponding to a second hash value from among these two or more identical hash values when there are said two or more identical hash values,
• migrating data stored in files stored in said one or more first logical storage devices to said one or more second logical storage devices, by not migrating first data of said first file to any of said one or more second logical storage devices, and migrating second data of said second file to any of said one or more second logical storage devices.