You can’t choose the correct hard drive or the correct drive carrier until you actually know what size drive bay your server has. You should know that before you start ordering hard drives. How can you check this? Simple: press the release button, open the release handle, and slide the hard drive with its drive carrier out of the server. Just measure it. Do you have 2.5-inch or 3.5-inch drives? The hot-plug hard drive needs a drive carrier to connect the hard drive to the server backplane. The backplane is connected to a DELL PERC RAID Controller, and RAID volume can be created or adjusted from the RAID controller menu after installation. But what about standalone backplanes? Not all entry-level Dell PowerEdge servers have hot-plug backplanes. With a standalone backplane, hard drives are complete inside the server, and cables are connected directly to the hard drive connectors. On smaller Dell servers with basic controllers, hard drives are cabled one-by-one. Cabled hard drives aren’t hot-swappable.