How exactly does a SAS SFF-8087 breakout cable work? + RAID/connection questions
Solution 1:
A few items to help clarify SAS technology...
- SATA drives can connect to SAS ports.
- SAS drives cannot connect to SATA ports.
- Server-class hardware typically uses an embedded RAID controller or a separate RAID controller PCIe device.
- Most RAID controllers and SAS HBAs will use SAS connections (multilane or 4-lane SAS ports).
- Internally, these systems will use one of the internal SAS transports (SFF-8087 or SFF-8484) for cabling.
- 4-lane SAS cables carry FOUR SAS links over the same cable.
- Enterprise servers will typically have a SAS backplane for hot-swap hard drives. These backplanes can accommodate SAS and SATA disks. The backplanes also provide power to the drives. It doesn't make sense to run SATA cables to hot-swappable hard drives. Instead, the internal SAS cables will link the controller and the backplane.
- You can mix and match SATA and SAS on the same backplane, but because the protocols are different, bad things. can happen.
Internal SAS 4-lane cabling to a backplane
Internal SAS breakout cabling to a backplane
