Patent ID: 8626978

Claim:
A computer apparatus comprising: a plurality of computer modules including processing devices; an I/O adapter; a switch including an upstream port connected to the computer modules and a downstream port connected to the I/O adapter; and a PCI manager, wherein the switch includes a virtual switch logically connecting the upstream port and the downstream port, and stores a first identifier assigned to a connection path between a first computer module in an operating state and a first virtual switch and a second identifier assigned to a connection path between the first virtual switch and the I/O adapter, wherein when the first computer module in the operating state moves to a non-operating state, the PCI manager detecting the non-operating state moves to a non-operating state, the PCI manager detecting the non-operating state issues an assignment update instruction of the first and second identifiers to the switch, wherein the switch that received the assignment update instruction of the first and second identifiers carries over and assigns the first identifier to a connection path between a second computer module in a standby state and a second virtual switch, and carries over and assigns the second identifier to a connection path between the second virtual switch and the I/O adapter, and wherein the second computer module moves to the operating state after the carryovers of the first and second identifiers in the second virtual switch, and takes over and uses the I/O adapter that was used by the first computer module.