Patent ID: 7453816

Claim:
A method in a data processing system for automatic recovery from a failed node concurrent maintenance add operation, the method comprising: disabling communications between a plurality of processor nodes in the data processing system; sending, by a control logic, a first test command to processors of a new processor node to be added to the data processing system; detecting, by the control logic, one of a response from the processors of the new processor node and a timeout; responsive to detecting the response from the processors of the new processor node, determining, by the control logic, if the response is a correct response matching the first test command; responsive to a correct response, updating, by the control logic, values of a current mode register, wherein the values comprise configuration settings of processors of the new processor node; updating, by the control logic, all processors in the plurality of processor nodes to use values of the current mode register; sending, by the control logic, a second test command to all processors in the plurality of processor nodes; detecting, by the control logic, one of a response from all processors in the plurality of processors and a timeout; determining, by the control logic, if the response is a correct response matching the second test command; and responsive to a correct response, initializing, by the control logic, communications between the plurality of processor nodes in the data processing system including the new processor node.