Data migration method, protocol converter and switching apparatus using it

• US 20020002638A1
• Filed: 02/12/2001
• Published: 01/03/2002
• Est. Priority Date: 06/29/2000
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Obara, Kiyohiro
• Granted Patent: US 6,708,232 B2
• Time in Patent Office: Days
• US Class Current: 710/11
• CPC Class Codes: G06F 2003/0697 device management, e.g. handlers, drivers, I/O schedulers
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion

Abstract

An online data migration method is provided for transferring data from a computer and an existing storage system using the conventional interface such as SCSI to a new storage system using SAN. The present method comprises the steps of disconnecting the connection between the computer and the first storage system with first interface protocol, connecting the computer to a switch connected to a second storage system with a second interface protocol through first protocol converter having protocol converting facility, connecting the switch to the first storage system through second protocol converter, and migrating data in the first storage system into the second storage system via the switch.

Claims

1. A data migration method, comprising the steps of:

disconnecting a connection between a computer performing data transfer by a first communication protocol and a first storage system performing data transfer by the first communication protocol;

connecting, through a first protocol converter, said computer to a switch connected to a second storage system performing data transfer by a second communication protocol;

connecting, through a second protocol converter, said switch to said first storage system; and

migrating, through said switch, data stored in said first storage system into said second storage system,

wherein said first and second protocol converters have a protocol converting function for converting the first communication protocol into the second communication protocol and vice versa, the second communication protocol into the first communication protocol.

2. A data migration method according to claim 1, wherein:

said first protocol converter has a first conversion function for converting a second identifier used by said second storage system that performs data transfer by the second communication protocol into a first identifier for performing data transfer by the first communication protocol, and a first translation table for converting between the first and the second identifiers;

said first protocol converter, said second protocol converter and said switch form a switching apparatus,

said switching apparatus performs data exchange by using the first conversion function so that said computer performing data transfer by the first communication protocol may handle said second storage system as a storage system using the first communication protocol,

a second protocol converter has a second conversion function for converting a third identifier used by the first storage system that performs data transfer by the first communication protocol into a fourth identifier for performing data transfer by the second communication protocol, and a second translation table for converting between the third and the fourth identifiers; and

said switching apparatus performs data exchange by using the second conversion function so that said second storage system performing data transfer by the second communication protocol may handle said first storage system as a storage system using the second communication protocol.

3. A data migration method according to claim 1 or 2, in which:

said step of migrating, through said switch, the data stored in said first storage system into said second storage system is executed by an online data migration facility provided to said second storage system.

4. A data migration method according to claim 1 or 2, in which:

said step of migrating, through said switch, the data stored in said first storage system into said second storage system is executed by an online data migration facility provided to said switch.

5. A data migration method according to any one of claims 1 through 4, wherein:

said first storage system performing data transfer by the first communication protocol is a first disk drive performing data transfer by a first disk interface, and

said second storage system performing data transfer by the second communication protocol is a second disk drive performing data transfer by a second disk interface.

6. A data migration method according to claim 5, wherein:

said first disk interface is a SCSI protocol, and said second disk interface is a fiber channel protocol.

7. A protocol converter for converting a first communication protocol to a second communication protocol and vice versa, comprising:

a first interface unit for performing data transfer with a first device using the first communication protocol;

a second interface unit for performing data transfer with a second device using the second communication protocol;

a processor for performing first conversion which converts data from said second interface unit to data in the first communication protocol to output the data in the first communication protocol through said first interface unit, and for performing second conversion which converts data from said first interface unit to data in the second communication protocol to output the data in the second communication protocol through said second interface unit; and

a translation table for protocol conversion,

wherein said processor performs said first conversion by converting a second identifier of said second device into a first identifier for performing data transfer by the first communication protocol, and performs said second conversion by converting a third identifier of said first device into a fourth identifier for performing data transfer by the second communication protocol;

said translation table records the correspondence between the first and the second identifiers for said first conversion, and the correspondence between the third and the fourth identifiers for said second conversion.

9. A switching apparatus, comprising:

said protocol converter of claim 7 for converting the first communication protocol to the second communication protocol and vice versa, and

a switch operable in the second communication protocol for exchange, wherein

said switch is connected to the second interface unit of said protocol converter for performing data transfer with said second device using the second communication protocol.

8. A recording medium for storing a program for a protocol conversion which converts a first communication protocol to a second communication protocol and vice versa, the protocol conversion executed by a processor having a first interface unit for performing data transfer with a first device using the first communication protocol, a second interface unit for performing data transfer with a second device using the second communication protocol, and a translation table used for the protocol conversion,

wherein said program causes said processor to execute first conversion which converts data from said second interface unit into data in the first communication protocol to output the data in the first communication protocol through said first interface unit, and to execute second conversion which converts data from said first interface unit into data in the second communication protocol to output the data in the second communication protocol through said second interface unit, as well as to execute said first conversion by converting a second identifier of said second device into a first identifier for performing data transfer by the first communication protocol, and to execute said second conversion by converting a third identifier of said first device into a fourth identifier for performing data transfer by the second communication protocol,

wherein said translation table records the correspondence between the first and the second identifiers for said first conversion as well as the correspondence between said third and the fourth identifiers for said second conversion.