SAS-2 6Gbps Maximum Disk Capacity

Question

So I think this should be a simple enough question but my google-fu is not turning up an answer.

I am wondering what the maximum size a single physical disk can be under the SAS-2 6Gbps spec. I remember from past experience that a SAS-1 controller will see only the first 2 TB of a disk which is larger. I am putting together a backup server which uses SAS-2 controllers and expander backplanes. Given the application, I'm looking for storage density over performance but I don't want to buy drives that are larger than my controllers can address.

score 1 · Accepted Answer · answered Mar 31 '16 at 21:15

1

SAS (all speeds) uses LBA48 so the maximum single disk size with the increasingly out of date 512-byte sector layout would be 128PB, the 4K-byte sectors as seen on modern disks this rises to 1EB.

answered Mar 31 '16 at 21:15

Chopper3

101,651

Thanks for the helpful info Chopper! So the previous limitation was probably related to my controller as ewwhite stated? Rather than the SAS spec? – Jarred Masterson Mar 31 '16 at 21:23

score 0 · Answer 2 · answered Mar 31 '16 at 20:36

Um, it depends on what controllers you use, and the age/version/firmware.

The disk capacity is unrelated to the SAS specification.

Use the largest disks that meet your capacity, performance and cost needs. Right now, that's probably 4TB, 6TB, 8TB disks.

SAS-2 6Gbps Maximum Disk Capacity

2 Answers2