APAR statusClosed as program error.Error descriptionThere is a weakness in the thread liveness monitoring logic oftwo of the Topology Services modules which could cause thesubsystem to perceive the loss of a neighbor to be caused atleast in part by a local process hang.  As a result, thesubsystem will deliberately allow the DMS to expire to preventdata corruption caused by a sundered network. The affected network modules are Disk Heartbeating (whichincludes Multi-Node Disk Heartbeating) and rs232 (also knownas TTY). The thread monitoring error only exists at RSCT level 2.5.4.0(or higher) on AIX 6.1, or 2.4.12.0 (or higher) on AIX 5.3-- it should be noted that these levels are the minimumrequired to run PowerHA 6.1. This problem might be seen during failover tests when a nodeis halted or powered off, depending on the Failure DetectionRate (FDR) on the affected network, as well as the value of theDMS timeout.  It is somewhat more likely to be seen with theDisk Heartbeating network than with rs232.