Dust bunny jumper
New to a MSP job, I go to troubleshoot a client's RAID alarm on a Netware 3.11 server. Reboot and get into the RAID console and notice that the SCSI ID on the drives seemed a little odd. They started in order, but then skipped a couple of IDs and listed the last drive last or nearly so. That was the drive it was claiming was missing from the array, but obviously it was present. I wondered what the tech who set the server up was thinking by skipping IDs. I downed the server and opened the case to check the SCSI ID jumpers, and that drive had a dust bunny perfectly jumping the higher ID! Nearly a full can of compressed air later, booted the server back up with all drives correctly ID'ed and off it went to rebuild the array.