Why is a SATA HDD listed as sda?
 

The harddrive in this PC is a WD400BD, with a SATA connection to
the mainboard.
So why does
fdisk -l

list the partitions as /dev/sda1, /dev/sda2, etc?
Is it really a SCSI drive?
Thanks.

sata = serial ATA, and serial is what the s in sda represents to the best of my knowledge. Sata drives will be sdX devices on all standard operating systems unless some weird stuff is being done under the covers.

From what I know, both SCSI and SATA have similar naming, /dev/sd*

CentOS still uses hd? and sd? -- messes me up at times
I think everyone else uses only sd? for both ( except in the grub.conf )

Originally IDE disks (parallel ATA) were identified with /dev/hdx and scsi disks with /dev/sdx, because of the complete different interfaces.

After some time work started on a unified interface for disks. Result of this work is that most P-ATA and S-ATA disks got a scsi compatibility layer. (They act as a scsi drive towards the OS).

Result of this is that on the newest distributions there are only /dev/sdx devices.

For example my server which has an IDE and a SATA drive shows them as /dev/sda (IDE) and /dev/sdb (SATA) under OpenSuse 11.3.
As for that the IDE cd-rom player will show up as /dev/sr0 (sr=scsi rom)

note1) and no, the s in sda stands for scsi which predates sata for a very long time

note2) Yeah, but grub will use hd(x,x) no matter if it's scsi, pata or sata.

_______________
Gerrard

Doh! I thought it meant "serial", not "sata" though. I'd actually have no idea how to clarify what I said either way. Some c header somehwere with an ancient comment in it I guess

I think it has more how the disto was setup. At some point most distro's changed how the drives are "seen". They are seen as scsi would be my opinion if it is sda. Even usb devices are considered scsi only in they way the software interacts with them. That is on most newer distros.

Thanks for all of your answers, and I did have the clue that Debian fdisk -l lists my SDCardReader as /dev/sdb so, yes, the card reader is listed similarly as the SATA drive.
I added an old Quantum Fireball 1.3 gigabyte drive as an IDE slave, with a CD-RW as the IDE master, and GRUB, was installed on that old 1.3 gibabyte drive.
Another question I have about this drive is that it has a 4 pin MOLEX power connector AND a 15 pin power connector attached, yet the drive seems to run OK with either the 4 pin connector or the 15 pin SATA connector.
Should the drive have BOTH power connectors?
The very short wire lengths between the 4 pin and 15 connectors, for each pair of them in the wiring harness, seems to preclude the possibility of connecting all FOUR power connectors to a pair of SATA drives, if I add a second SATA drive...)
So I'm guessing that only 1 power connector per drive is OK.