In certain system arrangements duplicated buffer memory units are employed in an active-standby configuration to reduce so-called "down time" in the presence of a failure and, thereby, improve system reliability. In such duplicated memory system arrangements proper system operation requires that the contents of each of the memory units be identical. Prior arrangements are known in which synchronization of such duplicated memory units is realized. (See, for example, U.S. patent application Ser. No. 07/739,928, filed Aug. 2, 1991 now U.S. Pat No. 5,278,969 issued Jan. 11, 1994.) It should be noted that ATM transmission of data is on a cell-by-cell basis wherein each cell comprises a fixed length packet. Thus, in the ATM context, the terms cell and packet are interchangeable. In the noted prior duplicated memory arrangement, a plurality of queues is employed to store cells, with each of the queues being associated on a one-to-one basis with either inputs or outputs of the memory unit. Synchronization of the active and standby memory units is realized in this prior arrangement by employing a queue length counter with each queue and observing when all of the counters have reached zero count at least once. Although this prior arrangement will indicate that the duplicated memories are in synchronization at some particular time after synchronization has been initiated, it does not determine when or how to initiate resynchronization. Once synchronization has been obtained, if the contents of the corresponding queues in the active and standby memories become different during any cell interval, problems can arise.