op_read error on parent context: generic socket fa
 

what does it mean? It appears when Fluent was iterating. op_read error on parent context: generic socket failure, error stack: MPIDU_Sock_wait(2533): Periodo di timeout del semaforo scaduto. (errno 121) unable to read the cmd header on the parent context, generic socket failure, error stack: MPIDU_Sock_wait(2533): Periodo di timeout del semaforo scaduto. (errno 121). connection to my parent broken, aborting. state machine failed. Please answer me.