Is there an actual difference between a CRC error and a FCS error?
After reading a lot, they seem like the same thing, but most switches and readings refer to them as separate entities.
Is there an overlap of these counters on a switch interface?
It was my understanding that CRC is the algorithm that FCS uses to do its check. Meaning that the Frame Relay, PPP and other protocols have the CRC to be used as the algorithm to calculate the FCS as defined in their standard. Other protocols could include a FCS but use a different algorithm besides CRC.