Partial and complete local diagnosis in computer systems with circulant structure

System diagnosis at multiple faults of multiplicity not greater than $t$ is considered. The conditions when the state of each system module is only determined by the testing rusults of the physically connected modules (self-determination conditions) are analysed. The diagnosability conditions are established for the case when the self-determination conditions are not satisfied for any module. A new class of locally $(t_r/t)$-diagnosable systems is introduced, where $t$ is the fault multiplicity and $t_r$ is the multiplicity of faults at which the states of all system modules can be determined correctly and completely. The values of $t_r$ are estimated. It is shown that the local $t$-diagnosability can be achieved by the system test redundancy.