Booting from a remote BIOS image

1. A method, comprising:

intercepting a request for a local Basic Input/Output System (BIOS) image of a computer system by a controller of the computer system;

retrieving a remote BIOS image for the computer system from a remote computer system communicatively coupled to the computer system via the controller;

executing the remote BIOS image by the computer system;

intercepting a write request to a non-volatile storage of the computer system; and

sending a remote BIOS image update to the remote computer system based on the write request.

2. The method of claim 1 , further comprising:

intercepting a read request to a non-volatile storage of the computer system; and

reading the remote BIOS image based on the read request.

3. The method of claim 2 , wherein reading the remote BIOS image includes reading a cached remote BIOS image cached at the computer system.

4. The method of claim 1 ,

a wherein the remote BIOS image update is sent to the remote computer system based on the write request if the remote BIOS image stored on the remote computer system has not changed since the remote BIOS image was retrieved.

5. The method of claim 4 wherein determining if the remote BIOS image stored on the remote computer system has not changed includes determining if a stored checksum associated with the remote BIOS image on the computer system matches a current checksum of the remote BIOS image on the remote computer system.

6. The method of claim 4 , further comprising sending the remote BIOS image update to the remote computer system if the write request updates only one or more non-volatile variables associated with the remote BIOS image.

7. The method of claim 4 , further comprising failing the write request if the remote BIOS image stored on the remote computer system has changed since the remote BIOS image was retrieved and if the write request updates other than one or more non-volatile variables associated with the remote BIOS image.

8. The method of claim 1 wherein in the computer system does not include a non-volatile storage having stored the local BIOS image.

9. An article of manufacture comprising:

a machine-accessible recordable/non-recordable medium that stores a plurality of instructions which when executed perform operations comprising:

intercepting a request for a local Basic Input/Output System (BIOS) image of a computer system during a pre-boot phase of the computer system;

retrieving a remote BIOS image for the computer system from a remote computer system communicatively coupled to the computer system during the pre-boot phase;

intercepting a write request to a non-volatile storage of the computer system; and

sending a remote BIOS image update to the remote computer system based on the wnte request.

10. The article of manufacture of claim 9 wherein execution of the plurality of instructions further perform operations comprising caching the remote BIOS image at the computer system.

11. The article of manufacture of claim 10 wherein execution of the plurality of instructions further perform operations comprising

intercepting a read request to a non-volatile storage of the computer system; and

using the cached remote BIOS image to respond to the read request.

12. The article of manufacture of claim 9 wherein execution of the plurality of instructions further perform operations comprising:

sending a remote BIOS image update to the remote computer system based on the write request if the remote B LOS image stored on the remote computer system has not changed since the remote BIOS image was retrieved.

13. The article of manufacture of claim 12 wherein determining if the remote BIOS image stored on the remote computer system has not changed includes determining if a stored checksum associated with the remote BIOS image on the computer system matches a current checksum of the remote BIOS image on the remote computer system.

14. The article of manufacture of claim 12 wherein execution of the plurality of instructions further perform operations comprising sending the remote BIOS image update to the remote computer system if the write request updates only one or more non-volatile variables associated with the remote BIOS image.

15. The article of manufacture of claim 12 wherein execution of the plurality of instructions further perform operations comprising failing the write request if the remotc BIOS image stored on the remote computer system has changed since the remote BIOS image was retrieved and if the write request updates other than one or more non-volatile variables associated with the remote BIOS image.

16. The article of manufacture of claim 9 wherein intercepting the request for the local BIOS image includes monitoring a Serial Peripheral Interface (SPI) bus of the computer system during the pre-boot phase for a start vector associated with the local BIOS image.

17. A computer system, comprising:

a flash memory device having stored a local Basic Input/Output System (BIOS) image for the computer system; and

a controller operatively coupled to the flash memory device, the controller including:

a processor;

a controller network interface operatively coupled to the processor; and

a non-volatile storage operatively coupled to the processor, the non-volatile storage including firmware instructions which when executed by the processor perform operations comprising:

intercepting a request to the flash memory device for the local BIOS image;

retrieving a remote BIOS image for the computer system from a server communicatively coupled to the computer system at the controller network interface;

intercepting a write request to a non-volatile storage of the computer system; and

sending a remote BIOS image update to the remote computer system based on the write request.

18. The computer system of claim 17 wherein the controller network interface to serve as a manageability port accessible by the server to conduct network management tasks associated with the computer system.

19. The computer system of claim 17 wherein execution of the firmware instructions further perform operations comprising:

intercepting a read request to the flash memory device; and

reading the remote BIOS image based on the read request.

20. The computer system of claim 19 reading the remote BIOS image includes reading a cached remote BIOS image cached at the computer system.

21. The computer system of claim 17 wherein execution of the firmware instructions further perform operations comprising:

sending a remote BIOS image update to the server based on the write request using the controller network interface if the remote BIOS image stored on the server has not changed since the remote BIOS image was retrieved.

22. The computer system of claim 21 wherein determining if the remote BIOS image stored on the server has not changed includes determining if a stored checksum associated with the remote BIOS image on the computer system matches a current checksum of the remote BIOS image on the server.

23. The computer system of claim 22 wherein execution of the firmware instructions further perform operations comprising:

updating the stored checksum based on the remote BIOS image update; and

updating a cached remote BIOS image at the computer system based on the remote BIOS image update.

24. The computer system of claim 21 wherein execution of the firmware instructions further perform operations comprising sending the remote BIOS image update to the server using the controller network interface if the write request updates only one or more non-volatile variables associated with the remote BIOS image.

25. The computer system of claim 21 whcrein execution of the firmware instructions further perform operations comprising failing the write request if the remote BIOS image stored on the server has changed since the remote BIOS image was retrieved and if the write request updates other than one or more non-volatile variables associated with the remote BIOS image.