Data protection in a data storage system
Systems and methods herein provide for protecting data using snapshots and images of those snapshots to quickly recreate data upon request. For example, a storage controller of a data storage system allocates a period of time between creating snapshots of data in a first storage volume of the data storage system. The controller then logs received write requests to the first storage volume and generates snapshot of data in the first storage volume based on the allocated period of time. Thereafter, the controller may receive a request to recreate data. The controller locates the snapshot in the first storage volume based on that request to recreate the data. In doing so, the controller generates a snapshot image in a second storage volume. The controller then retrieves logged write requests and applies them to the snapshot image to recreate the data in the second storage volume.
1. A method of protecting data in a data storage system, the method comprising:
allocating a period of time between creating snapshots of data in a first storage volume;
receiving and logging write requests to the first storage volume;
generating a snapshot of data in the first storage volume after the allocated period of time;
receiving a request to recreate data;
locating the snapshot of data in the first storage volume based on the request to recreate the data;
generating a snapshot image in a second storage volume based on the located snapshot, wherein the snapshot image comprises data obtained from the located snapshot;
retrieving logged write requests received after the snapshot was generated; and
applying the logged write requests to the snapshot image to recreate the data of the first storage volume in the second storage volume.
2. The method of claim 1 , further including logging subsequently received write requests and directing the subsequently received write requests to the first and second storage volumes.
3. The method of claim 1 , further including comparing the second storage volume to the first storage volume after recreating the data in the second storage volume to determine inconsistency between the two volumes.
4. The method of claim 3 , further comprising ceasing write requests to the first storage volume upon determining said inconsistency between the two volumes.
5. The method of claim 3 , further including presenting the comparison to an end user.
6. The method of claim 1 , wherein the data storage system is a virtualized data storage system.
7. The method of claim 1 , further comprising:
generating a journal to log the write requests; and
storing the journal in: the first storage volume; the second storage volume; memory of a storage controller; memory of a network computing device; or a combination thereof.
8. The method of claim 7 , further comprising generating a lookup table that includes information about each received write request in the journal associated with the snapshot to identify a location of the write requests.
9. The method of claim 1 , further comprising processing the request to recreate data to extract a time stamp in the request and identify the snapshot.
10. The method of claim 1 , wherein the allocated period of time between snapshots is constant.
11. The method of claim 1 , wherein the allocated period of time between snapshots is variable.
12. A data storage system, comprising:
first and second storage volumes operable to store data;
a controller communicatively coupled to the first and second storage volumes, wherein the controller is operable to manage read requests and write requests to the first and second storage volumes, the controller comprising a data protection module operable to log the write requests to the first storage volume, generate a snapshot of data in the first storage volume after an allocated period of time, receive a request to recreate data, locate the snapshot of data in the first storage volume based on the request to recreate data, and generate a snapshot image in the second storage volume based on the located snapshot, wherein the data protection module is further operable to retrieve logged write requests received after the snapshot was generated and apply the logged write requests to the snapshot image to recreate data of the first storage volume in the second storage volume.
13. The data storage system of claim 12 , wherein the data protection module is further operable to log subsequently received write requests and directing the subsequently received write requests to the first and second storage volumes.
14. The data storage system of claim 12 , or in the data protection module is further operable to compare the second storage volume to the first storage volume after recreating the data in the second storage volume to determine inconsistency between the two volumes.
15. The data storage system of claim 14 , wherein the data protection module is further operable to cease write requests to the first storage volume upon determining said inconsistency between the two volumes.
16. The data storage system of claim 12 , wherein the data storage system is a virtualized data storage system.
17. The data storage system of claim 12 , wherein the data protection module is further operable to generate a journal to log the write requests and store the journal in: the first storage volume; the second storage volume; memory of a storage controller; memory of a network computing device; or a combination thereof.
18. The data storage system of claim 17 , wherein the data protection module is further operable to generate a lookup table that includes information about each received write request in the journal associated with the snapshot to identify a location of the write requests.
19. The data storage system of claim 12 , wherein the data protection module is further operable to process the request to recreate data to extract a time stamp in the request and identify the snapshot.
20. A computer readable medium operable to store a software product for use within a virtualized storage system controller, the software product comprising instructions for directing the virtualized storage system controller to:
receive and log write requests to a first storage volume of the virtualized storage system;
generate snapshots of data in the first storage volume after allocated periods of time;
receive a request to recreate data of the first storage volume;
locate one of the snapshots of data in the first storage volume based on the request to recreate the data;
generate a snapshot image in a second storage volume of the virtualized storage system based on the located snapshot;
retrieve logged write requests received after the located snapshot was generated; and
apply the logged write requests to the snapshot image to recreate the data of the first storage volume in the second storage volume.