On February 11th, we had a disk-related failure that incidentally led to one of the network-related crashes discussed in another post. When a new drive was inserted into a server, three other drives were thrown from the RAID at the same time. Two came back; one did not. The three disks were all in the right-side of the server.

We found out later that the disk in the middle right-hand bay of this chassis did not fit correctly. We believe this deformed the disk backplane such that the physical connections on the right side were marginal.

This appeared to be related to a 2.5” -> 3.5” adapter, because a normal 3.5” hard drive did not have the issue. This adapter worked easily with all the chassis drive bays, excluding that particular bay on the middle right-hand side.

We found that not all of the 2.5” -> 3.5” adapters we own have the same issue. Comparing them, we believe this is a defect that Supermicro found and fixed without updating the part number. The specific part number is MCP-220-00043-0N. Inside of the adapter on the upper right corner, bad adapters have the ID “01-SC81523-XX00C001.” The good drive adapters have the ID “01-SC81523-XX00C103.”

Manufacturers, please at least add a revision to the original model number if you can’t change anything else. In every single case I’ve had to deal with this (and this is not the first), it’s extremely difficult to buy the right part otherwise. If the part number doesn’t change, your customers also don’t know that they need to go through a new qualification process.