Optimized disaster-recovery-as-a-service system

1. A computer implemented method comprising:

ascertaining, by one or more processor running on a source site, one or more selected service for the source site amongst one or more provided service offered by a target site;

recording, by the one or more processor, changes in the source site of client data that are relevant to a selected service of the one or more selected service based a policy for the selected service as configured by the target site, wherein the changes in the source site of the client data include changed client data resulting from input/output requests while the source site services end users; and

supplying, by the one or more processor, the changes of the client data from the recording to the target site that performs the selected service for a client site, wherein the policy classifies the client data into a plurality of components, and wherein the policy associates each of the components of the client data with a respective essentialness score as being assessed in the context of respective impact of the components on performing the selected service at the target site.

2. The computer implemented method of claim 1 , the ascertaining comprising:

obtaining information on the one or more selected service from a client of the source site by prompting the client with the one or more provided service.

3. The computer implemented method of claim 1 , the ascertaining comprising:

receiving a demand to perform the one or more selected service from a client of the source site service in preparation of a specific occasion.

4. The computer implemented method of claim 1 , wherein the one or more provided service is selected from the group consisting of a disaster recovery service and at least one value-added service, and wherein the at least one value-added service comprising:

a virus scanning service, an eDiscovery service, a compressibility estimation service.

5. The computer implemented method of claim 1 , wherein the respective essentialness score associated with each of the components of the client data is classified into three degrees, wherein the highest essentialness score indicates that any component of the client data having the highest essentialness score must be present at the target site to perform the selected service, wherein a next highest essentialness score indicates that any component having the next highest essentialness score is not necessary at the target site but can be beneficial to perform the selected service, and wherein a lowest essentialness score indicates that any component having the lowest essentialness score has no impact on performing the selected service at the target site.

6. The computer implemented method of claim 1 , wherein the changed data in the source site of the client data includes changed client data resulting from file changes while the source site services end users.

7. The computer implemented method of claim 1 , wherein the changed data in the source site of the client data includes changed client data resulting from root disk file changes and data disk file changes while the source site services end users.

8. The computer implemented method of claim 1 , wherein the components of the client data that are scored with respective essentialness scores include a virtual machine component, a storage volume component, and an application program component.

9. The computer implemented method of claim 1 , wherein a first component of the components of the client data is scored with a score of “essential”, a second component of the components of the client data is scored with a score of “valuable” and third component of the components of the client data is scored with a score of “non-essential”.

10. The computer implemented method of claim 1 , wherein the method includes performing essentialness assessment of a first component of the components of the client data to produce a first essentialness score of the first component, and wherein the method includes assessing a second component of the client data to produce a second essentialness score for the second component, wherein the performing the essentialness assessment includes performing the essentialness assessment in dependence on a type of the service.

11. A computer program product comprising:

a computer readable storage medium readable by one or more processor and storing instructions for execution by the one or more processor for performing a method comprising:

ascertaining, on a source site, one or more selected service for the source site amongst one or more provided service offered by a target site;

recording changes in a client site of client data that are relevant to a selected service of the one or more selected service based a policy for the selected service as configured by the target site; and

supplying the changes of the client data from the recording to the target site that performs the selected service for the client site.

12. The computer program product of claim 11 , wherein the policy dictates a manner in which how the changes, respective to components in the client data, are to be replicated to the target site in order to minimize a cost to perform the selected service at the target site.

13. The computer program product of claim 11 , wherein the policy classifies the client data into a plurality of components, and wherein the policy associates each of the components of the client data with a respective essentialness score as being assessed in the context of respective impact of the components on performing the selected service at the target site.

14. The computer program product of claim 13 , wherein the respective essentialness score associated with each of the components of the client data is classified into three degrees, wherein the highest essentialness score indicates that any component of the client data having the highest essentialness score must be present at the target site to perform the selected service, wherein a next highest essentialness score indicates that any component having the next highest essentialness score is not necessary at the target site but can be beneficial to perform the selected service, and wherein a lowest essentialness score indicates that any component having the lowest essentialness score has no impact on performing the selected service at the target site.

15. The computer program product of claim 13 , wherein the respective essentialness score associated with respective ones of the components of the client data is classified into a first essentialness score specifying a first degree of essentialness and a second score specifying a second degree of essentialness, wherein the first essentialness score indicates that any component of the client data having the first essentialness score must be present at the target site to perform the selected service, wherein the second essentialness score indicates that any component having the second essentialness score is not necessary at the target site but can be beneficial to perform the selected service.

16. The computer program product of claim 13 , wherein the respective essentialness score associated with respective ones of the components of the client data is classified into a first essentialness score specifying a first degree of essentialness and a second score specifying a second degree of essentialness, wherein the first essentialness score indicates that any component of the client data having the first essentialness score must be present at the target site to perform the selected service, wherein the second essentialness score indicates that any component having the lowest essentialness score has no impact on performing the selected service at the target site.

17. The computer program product of claim 11 , wherein the method includes assigning a first essentialness score to a first component of the client data, and assigning a second essentialness score to a second component of the client data, the second essentialness score indicating a degree of essentialness lower than the first essentialness score, wherein the method includes replicating the first component on the target site in dependence on the first essentialness score, and reconstructing the second component on the target site in dependence on the second essentialness score.

18. The computer program product of claim 11 , wherein the method includes assigning a first essentialness score to a first component of the client data, and assigning a second essentialness score to a second component of the client data, the second essentialness score indicating a degree of essentialness lower than the first essentialness score, wherein the method includes based on the second essentialness score for the second component, replicating the second component on the target site responsively to a result of a process to analyze network traffic, and based on the first essentialness score for the first component, replicating the first component on the target site independently of the result of the process to analyze network traffic.

19. A system comprising:

a memory;

one or more processor in communication with the memory; and

program instructions executable by the one or more processor via the memory to perform a method comprising:

ascertaining, on a source site, one or more selected service for the source site amongst one or more provided service offered by a target site, wherein the one or more selected service includes a disaster recovery service;

recording changes in the source site of client data that are relevant to a selected service of the one or more selected service based on a policy for the selected service as configured by the target site; and

supplying the changes of the client data from the recording to the target site that performs the selected service for a client site; and

performing the disaster recovery service in the target site by use of one or more of a replicated data volume, replicated log volume, or a reconstructed index volume.