1. A clustered computer system, comprising: a cluster of two or more nodes, the cluster comprising: at least a first node computer comprising a first processor and a first computer readable medium, the first computer readable medium having a first set of software comprising: an operating system executable by the first processor; clusterware program executable by the first processor to allow the first node computer to operate as part of a cluster environment; and an application program executable by the first processor to provide application services as part of the cluster environment; a second node computer independent of and new to the cluster, the second node computer comprising; a second processor; and a second computer readable medium having a second set of software; and a control computer in communication with the second node computer and the cluster, the control computer comprising a third processor and a third computer readable medium, the third computer readable medium comprising instructions executable by the third processor to: validate the second node computer to determine whether the second set of software and hardware of the second node computer meets hardware and software requirements for participation in the cluster environment, wherein validating the second node computer comprises reading a first input file having a first plurality of validation test identifiers identifying first validation tests to validate whether a system environment's level of system resources meet a minimum requirement, wherein the minimum requirement indicates a minimum level of system resources required for the system environment to support installation of a first software application, wherein the first validation tests are associated with the first software application, reading a first rule mapping file to obtain a first mapping between a first validation test identifier and a first program code identifier identifying first program code for performing at least a portion of the first validation tests, executing the first program code to perform the at least a portion of the first validation tests to determine whether the system environment's system resources meet the minimum requirement, reading a second input file having a second plurality of validation test identifiers identifying second validation tests to validate the system environment for a second software application, reading a second rule mapping file to obtain a second mapping between a second validation test identifier and a second program code identifier identifying second program code for performing at least a portion of the second validation tests, executing the second program code to perform the at least a portion of the second validation tests to validate the system environment for the second software application, and outputting results of the validation tests; and configure the second set of software to allow the second node computer to join the cluster if the second node computer is validated, wherein the second node computer communicates with the first node computer after joining the cluster.