Method and apparatus for determining compatibility between a virtualized application and a base environment

• US 8,090,744 B1
• Filed: 08/26/2009
• Issued: 01/03/2012
• Est. Priority Date: 08/26/2009
• Status: Expired due to Fees

• Current Assignee: CA, Inc. (d/b/a CA Technologies) (Broadcom, Inc.)
• Original Assignee: Symantec Operating Corporation (Gen Digital Inc.)
• Inventors: Baird, Bradley
• Primary Examiner(s): Lu, Kuen
• Assistant Examiner(s): Pham, Tuan A
• Application Number:
  US12/548,159
• Time in Patent Office: 860 Days
• Field of Search: None
• US Class Current: 707/791
• CPC Class Codes: G06F 16/1873 Versioning file systems, temporal file systems, e.g. file system supporting different historic versions of files
• CPC Class Codes: G06F 16/188 Virtual file systems
• CPC Class Codes: G06F 16/252 between a Database Management System and a front-end application

Abstract

A system and method for determining whether one or more applications in a virtual software layer and one or more applications in a base environment are compatible. The method includes intercepting an access attempt from an application on a computer system to a file on the computer system, such as a system file. The system then determines a first compatibility checking mode and whether a second version of the file exists in a virtual software layer. In response to these determinations and to intercepting the access attempt, the system attempts to perform the access using the second version of the file.

Claims

1. A computer-implemented method, comprising:

determining a set of files of a plurality of files stored on a computer system, wherein for each file in the set, a second version of the file exists in a virtual software layer of the computer system;

intercepting an access attempt from an application on the computer system to a first file on the computer system;

determining a first compatibility checking mode;

determining that a second version of the first file on the computer system exists in the virtual software layer, wherein determining that the second version of the first file on the computer system exists comprises determining that the second version of the first file is a member of the set, and wherein the second version of the first file has a same name as the first file; and

in response to said intercepting, said determining the first compatibility mode, and said determining that a second version of the system file exists, attempting to perform the access using the second version of the file.

2. The computer-implemented method of claim 1, wherein a file system path of the file is the same as a virtual path of the second version of the file.

3. The computer-implemented method of claim 1, wherein the application exists in a second virtual software layer distinct from the virtual software layer.

4. The computer-implemented method of claim 1, further comprising:

detecting that said attempting to perform the access failed, and in response to said detecting, recording an indication of the failure in an error log in a persistent storage space.

5. The computer-implemented method of claim 1, wherein the access attempt is performed by an automated test program configured to exercise a broad range of functionality provided by the application.

6. The computer implemented method of claim 1, further comprising:

overwriting the first file with the second version of the first file.

7. The computer-implemented method of claim 1, further comprising:

intercepting an access attempt from an application deployed in the virtual software layer to the second version of the first file on the computer system;

determining a second compatibility checking mode;

determining that the second version of the first file exists outside of the virtual software layer;

in response to said intercepting the attempt from the application deployed in the virtual software layer, said determining the second compatibility mode, and said determining that a second version of the system file exists outside of the virtual software layer, attempting to perform the access using the file.

8. A non-transitory computer-readable storage medium storing program instructions executable by a computer processor to perform:

determining a set of files of a plurality of files stored on a computer system, wherein for each file in the set, a second version of the file exists in a virtual software layer of the computer system;

intercepting an access attempt from an application on the computer system to a first file on the computer system;

determining a first compatibility checking mode;

determining that a second version of the first file on the computer system exists in the virtual software layer, wherein determining that the second version of the first file on the computer system exists comprises determining that the second version of the first file is a member of the set, and wherein the second version of the first file has a same name as the first file; and

in response to said intercepting, said determining the first compatibility mode, and said determining that a second version of the system file exists, attempting to perform the access using the second version of the file.

9. The computer-readable storage medium of claim 8, wherein a file system path of the file is the same as a virtual path of the second version of the file.

10. The computer-readable storage medium of claim 8, wherein the application exists in a second virtual software layer distinct from the virtual software layer.

11. The computer-readable storage medium of claim 8, wherein the program instructions are further executable to implement:

detecting that said attempting to perform the access failed, and in response to said detecting, recording an indication of the failure in an error log in a persistent storage space.

12. The computer-readable storage medium of claim 8, wherein the access attempt is performed by an automated test program configured to exercise a broad range of functionality provided by the application.

13. The computer-readable storage medium of claim 8, wherein the program instructions are further executable to implement:

overwriting the first file with the second version of the first file.

14. The computer-readable storage medium of claim 8, wherein the program instructions are further executable to implement:

intercepting an access attempt from an application deployed in the virtual software layer to the second version of the first file on the computer system;

determining a second compatibility checking mode;

determining that the second version of the first file exists outside of the virtual software layer;

in response to said intercepting the attempt from the application deployed in the virtual software layer, said determining the second compatibility mode, and said determining that a second version of the system file exists outside of the virtual software layer, attempting to perform the access using the file.

15. A system comprising:

one or more processors;

a memory coupled to the one or more processors, wherein the memory stores program instructions executable to implement;

a software virtualization system configured to support operation of a virtual software application in a virtual software layer;

a file system filter driver configured to intercept file system access attempts from the virtual software application and from another application not in the virtual software layer to respective system files;

wherein the file system driver is configured to determine a set of files of a plurality of files stored on the system, wherein for each file in the set, a second version of the file exists in the virtual software layer;

wherein the file system driver is configured to determine that a second version of a first file on the computer system exists in the virtual software layer, responsive to determining that the second version of the first file is a member of the set, and wherein the second version of the first file has a same name as the first file; and

wherein in a first mode of operation, the file system filter driver is configured to route an intercepted access attempt to the first file; and

wherein in a second mode of operation, the file system filter driver is configured to route the intercepted access attempt to the second file.

16. The system of claim 15, wherein the another application is in another virtual software layer, distinct from the virtual software layer.

17. The system of claim 15, wherein the file system filter is further configured detect whether one of the access attempts failed and in response, to record an indication of the failure in an error log in a persistent storage space.

18. The system of claim 15, wherein the program instructions are further executable to implement a testing module configured to exercise a broad range of functionality provided by the software application or by the virtual software application, wherein said exercising generates one or more of the access events.