Abstract: A tag server system provides unique tag values to many client systems. The tag server system comprises a processor that generates an inventory of unique tag values, such values being generated by monotonically increasing a value within the tag body field. A memory is provided for storing the inventory of unique tag values. A nonvolatile memory is controlled by the processor and stores a highest unique tag value generated by the processor. The processor implements a tag value recovery procedure and is responsive to a data loss failure mode in the tag server system to cause a readout of the highest unique tag value from the non-volatile memory. The processor is responsive to that highest unique tag value to commence generation of new unique tag values monotonically from that value and expends no effort to regenerate lost unique tag values that are less than the highest unique tag value derived from the non-volatile memory.