Making a boot drive for a first partition inaccessible to other partitions in a partitionable system

1. A computer program product comprising a non-volatile computer readable medium and non-transitory program instructions embodied therein, the program instructions being configured to be executable by a processor of a baseboard management controller in a multi-processor system to cause the processor to perform operations comprising:

causing, during a first time period, the multi-processor system to operate in a partitioned state with a first partitioned node including a first subset of components of the multi-processor system and a second partitioned node including a second subset of components of the multi-processor system, wherein the first and second partitioned nodes are independently operable nodes having their own operating systems, and wherein the first partitioned node boots from a first boot drive that is included in the first subset of components;

causing, during a second time period, the multi-processor system to operate in a unified state with a single unified node including components from both the first and second subsets of components of the multi-processor system, wherein the single unified node has its own operating system; and

causing the first boot drive to be inaccessible to the second partitioned node and the single unified node.

2. The computer program product of claim 1 , wherein the second partitioned node boots from a second boot drive that is included in the second subset of components, the operations further comprising:

causing the second boot drive to be inaccessible to the first partitioned node and the single unified node.

3. The computer program product of claim 1 , wherein the single unified node boots from a third boot drive in the multi-processor system, the operations further comprising:

causing the third boot drive to be inaccessible to the first partitioned node and the second partitioned node.

4. The computer program product of claim 1 , the operations further comprising:

storing a plurality of node definitions including a first node definition identifying the first subset of components included in the first partitioned node, a second node definition identifying the second subset of components included in the second partitioned node, and a third node definition identifying the components included in the single unified node;

providing the plurality of node definitions to an integrated circuit within the multi-processor system; and

instructing the integrated circuit to configure the multi-processor system in either the partitioned state using the first and second node definitions or the unified state using the third node definition.

5. The computer program product of claim 4 , wherein causing the first boot drive to be inaccessible to the second partitioned node and the single unified node includes preventing and/or removing the first boot drive from being included in either the second node definition or the third node definition.

6. The computer program product of claim 5 , the operations further comprising:

storing, in the plurality of node definitions, an entry associated with the first boot drive, wherein the entry indicates that the first boot drive is to be inaccessible to any node other than the first partitioned node.

7. The computer program product of claim 5 , wherein the second partitioned node boots from a second boot drive that is included in the second subset of components and the single unified node boots from a third boot drive in the multi-processor system, the operations further comprising:

causing the second boot drive to be inaccessible to the first partitioned node and the single unified node by preventing and/or removing the second boot drive from being included in either the first node definition or the third node definition; and

causing the third boot drive to be inaccessible to the first partitioned node and the second partitioned node by preventing and/or removing the third boot drive from being included in either the first node definition or the second node definition.

8. The computer program product of claim 4 , wherein the plurality of node definitions are user-configurable through a management interface.

9. The computer program product of claim 8 , the operations further comprising:

receiving user input establishing or modifying one or more of the plurality of node definitions.

10. The computer program product of claim 9 , the operations further comprising:

receiving user input designating one or more components in the first subset that are to be inaccessible to the second partitioned node and the single unified node.

11. The computer program product of claim 4 , the operations further comprising:

performing an inventory of components installed in the multi-processor system; and

populating a node definition table with the inventory of components.

12. The computer program product of claim 1 , the operations further comprising:

identifying the first boot drive by reading firmware interface settings for the first partitioned node.

13. The computer program product of claim 12 , wherein the first boot drive is a non-volatile data storage device storing the first operating system.

14. The computer program product of claim 1 , wherein the first partitioned node includes a distributed processing unit, the operations further comprising;

causing the distributed processing unit to be inaccessible to the second partitioned node and the single unified node.

15. The computer program product of claim 14 , wherein the distributed processing unit is a smart network interface controller that stores and runs its own operating system.

16. A method performed by a baseboard management controller in a multi-processor system, comprising:

causing, during a first time period, the multi-processor system to operate in a partitioned state with a first partitioned node including a first subset of components of the multi-processor system and a second partitioned node including a second subset of components of the multi-processor system, wherein the first and second partitioned nodes are independently operable nodes having their own operating systems, and wherein the first partitioned node boots from a first boot drive that is included in the first subset of components;

causing, during a second time period, the multi-processor system to operate in a unified state with a single unified node including components from both the first and second subsets of components of the multi-processor system, wherein the single unified node has its own operating system; and

causing the first boot drive to be inaccessible to the second partitioned node and the single unified node.

17. The method of claim 16 , wherein the second partitioned node boots from a second boot drive that is included in the second subset of components, the operations further comprising:

causing the second boot drive to be inaccessible to the first partitioned node and the single unified node.

18. The method of claim 16 , wherein the single unified node boots from a third boot drive in the multi-processor system, the operations further comprising:

causing the third boot drive to be inaccessible to the first partitioned node and the second partitioned node.

19. The method of claim 16 , the operations further comprising:

storing a plurality of node definitions including a first node definition identifying the first subset of components included in the first partitioned node, a second node definition identifying the second subset of components included in the second partitioned node, and a third node definition identifying the components included in the single unified node;

providing the plurality of node definitions to an integrated circuit within the multi-processor system; and

instructing the integrated circuit to configure the multi-processor system in either the partitioned state using the first and second node definitions or the unified state using the third node definition.

20. The method of claim 19 , wherein causing the first boot drive to be inaccessible to the second partitioned node and the single unified node includes preventing and/or removing the first boot drive from being included in either the second node definition or the third node definition.