You are not logged in.
I am building my first NAS (for home use), and using Arch. I'm getting it set up plan to use mdadm to set up an eight disk 2.5" SATAIII SSD in a RAID0. Since I'm new to this, I have kind of a generic hardware question about cables for connecting the SSDs to my HBA. The connectors I'm looking at are "Mini-SAS (SFF-8643) to 4x SATA III" cables. They are typically described as having a SFF-8643 connector (12Gbps) on one end and four SATA III connectors (6Gbps each for an aggregate of 24Gbps) on the other. See link for example picture: https://ae01.alicdn.com/kf/HTB1Lq_Pzh9Y … -Cable.jpg
I believe every sff-8643 connecter has 4 lanes. As such, is the connector capable of supporting 12Gbps on each lane for an an aggregate data rate of 48Gbps, and thus able to fully support each of four SATA III connectors simultaneously? Or is the connector limited to a total of 12Gbps, and as such bottlenecks the four SATA III connectors to 3Gbps?
I've found conflicting information from various sources. Many sources (perhaps most) suggest the connector is capable of an aggregate 48Gbps, while some sources, including a cable retailer who responded to my question, say it can only achieve a maximum of 12Gbps. I also I have tried to find the industry standards/specs, but can't seem to actually get at the technical info: https://www.snia.org/technology-communi … ifications.
Thoughts?
Offline
If you don't get a reply here, you might try the FreeNAS boards.
There are several people there who are very knowledgeable about HBAs, cabling, and data rates.
Cheers,
"Before Enlightenment chop wood, carry water. After Enlightenment chop wood, carry water." -- Zen proverb
Offline
