Method and apparatus for asynchronous mirroring using TCP/IP internet protocol
A system and method that mirrors data between two geographically separate locations. A preferred embodiment of the software includes three components: an AIM driver, an AIM service coordinator and an AIM manager. The AIM driver intercepts all disk I/Os to the local storage system and encapsulates the write transactions into a series of files. The AIM service coordinator transmits these files over any or all remote networks having remote storage systems connected to the local storage system and to which the data is to be mirrored. In a preferred embodiment, particular destinations for each write transaction may be user specified. These files, as they are received at the remote storage system, are placed into the file system of the remote storage system. The AIM service coordinator on the remote storage system detects the arrival of the files and accesses them. The content of these files (exact copies of the write transactions issued at the local system) are then re-driven within the remote storage system as write transactions to the remote disk drive, in exactly the same way as they would have occurred on the local storage system.
1. A system for mirroring write operations from a local storage system onto a remote storage system, the system comprising:
an asynchronous mirroring driver resident in the local storage system for intercepting I/O transactions to a storage disk of the local storage system, identifying a series of write transactions issued to said storage disk, making an exact copy of the series of write transactions, and storing said exact copy within a series of files that are created on a file-system of the local storage system; and
a first asynchronous mirroring coordinator resident on the local storage system for invoking a file transfer system to transmit the series of files on the local file-system of the local storage system to a file system of the remote storage system via a non-proprietary network protocol to accommodate an exact reproduction at the remote storage system of the series of write transactions as issued to said storage disk of the local storage system.
2. The system claim 1 further comprising:
a second asynchronous mirroring coordinator resident on the remote storage system for detecting the series of files on the file system of the remote storage system, opening the files and reading the exact copy of the series of write transactions in these files; and
an asynchronous mirroring driver resident on the remote storage system for receiving the exact copy of the series of write transactions from the second asynchronous mirroring coordinator and issuing the transactions to a remote device connected to the remote storage system which is configured to mirror the local storage device on the local storage system.
3. The system of claim 1 , wherein individual ones of the series of files comprise:
a Header portion that includes information on the total size of the file;
an I/O Control Block portion which indicates address offsets where each transaction in the file is to be stored on the remotely located destination storage system, and which further indicates the size of the data for each transaction; and
a Data portion which contains the data for each transaction in the file.
4. The system of claim 3 , wherein the Header portion further includes:
a pointer to the I/O Control Block portion which indicates the offset where the I/O Control Block portion of the file begins; and
a pointer to the Data portion, which indicates the offset where the Data portion of the file begins.
5. The system of claim 1 , wherein the asynchronous mirroring driver intercepts all I/O transactions in the system.
6. The system of claim 1 , wherein the asynchronous mirroring driver intercepts a transaction affecting the content or organization of a disk.
7. The computer program product of claim 1 , wherein the asynchronous mirroring driver module intercepts a transaction affecting the content or organization of a disk.
8. The system of claim 1 , wherein the series of write transactions is one of a plurality of series of I/O transactions that are respectively retained in corresponding ones of the series of files, and individual ones of the series of files include pointers to accommodate sequencing the series of files, whereby a transaction level record of changes to the storage disk of the local storage system is provided for the remote storage system.
9. The system of claim 8 , wherein the plurality of series of I/O transactions include at least one formatting transaction and/or at least one partitioning transaction.
10. A method for mirroring write operations from a local storage system to a remote storage system, the method comprising the steps of:
intercepting I/O transactions to a storage disk of the local storage system;
identifying a series of write transactions to said storage disk from the intercepted I/O transactions;
storing an exact copy of the series of write transactions within a series of files that are created on a file-system of the local storage system;
transmitting the series of files from the local storage system to the remote storage system through an Internet connection to accommodate a reproduction at the remote storage system of the series of write transactions as issued to said storage disk of the local storage system.
11. The method of claim 10 , further comprising:
passing the series of write transactions to a driver issuing the transactions to storage device of the remote storage system, which is configured to mirror the storage device on the local storage system.
12. The method of claim 10 , wherein intercepting I/O transactions comprises intercepting all I/O transactions in the system.
13. The method of claim 10 , wherein intercepting I/O transactions comprises intercepting a transaction affecting the content or organization of a disk.
14. The method of claim 10 , wherein the series of write transactions is one of a plurality of series of I/O transactions that are respectively retained in corresponding ones of the series of files, and individual ones of the series of files include pointers to accommodate sequencing the series of files, whereby a transaction level record of changes to the storage disk of the local storage system is provided for the remote storage system.
15. The method of claim 14 , wherein the plurality of series of I/O transactions include at least one formatting transaction and/or at least one partitioning transaction.
16. A computer program product for mirroring write operations from a local storage system to a remote storage system, the computer program product comprising:
an asynchronous mirroring driver software module for intercepting I/O transactions to a storage disk of the local storage system, identifying a series of write transactions issued to said storage disk, making an exact copy of the series of write transactions, and storing said exact copy within a series of files that are created on a file-system of the local storage system; and
a first asynchronous mirroring coordinator software module for invoking a configured file transfer system to transmit the series of files to a file system on the remote storage system via a non-proprietary network protocol to accommodate an exact reproduction at the remote storage system of the series of write transactions as issued to said storage disk of the local storage system.
17. The computer program product of claim 16 further comprising:
a second asynchronous mirroring coordinator software module installed on the remote storage system for detecting the series of files on the file system of the remote storage system, opening the files and reading the exact copy of the series of write transactions in these files, and issuing the exact copy of the series of write transactions to a storage device connected to the remote storage system that is configured to mirror the storage device on the local storage system.
18. The computer program product of claim 16 , wherein the asynchronous mirroring driver module intercepts all I/O transactions in the system.
19. The computer program product of claim 16 , wherein the series of write transactions is one of a plurality of series of I/O transactions that are respectively retained in corresponding ones of the series of files, and individual ones of the series of files include pointers to accommodate sequencing the series of files, whereby a transaction level record of changes to the storage disk of the local storage system is provided for the remote storage system.
20. The computer program product of claim 19 , wherein the plurality of series of I/O transactions include at least one formatting transaction and/or at least one partitioning transaction.