Trying to use SAS to SATA fan-out cable on Raid Controller
Posted on 2008-10-25
Okay, I'm fairly new to SAS, but far from new to SATA. I purchased a new raid controller for my file server last week, a Promise SuperTrak EX8650. The raid controller has two SAS ports on, however it also supports SATA. I ordered two Adaptec mSASx4 (SFF-8087) to SATA (4)x1 with sideband (SFF-8448) cables. Needless to say, I was in the office last night until about 3am before I gave up on it. When I plug the SAS to SATA cables in, then connect the drives, only the drives on the first two channels of the cable are recognized (Channels 0 & 1). I know all the drives are good, they're all brand new, plus if I move one of the working channels to another drive it also recognizes. This would be fine and dandy if i was only trying to connect 4 SATA drives, but I'm trying to connect (6) 1TB drives, setup in a raid 5. I toyed around with it for hours, trying everything I could possible think of, but all to no avail. The only thing I am not sure about is the 5th connector on these cables, the 'sideband'. I honestly have no idea what that is, but from what research I've done, it looks like its a type of connection used on a backplain...is this connection necessary? If-not, why would only the first two channels of both cables work? I know adaptec makes this same cable without the sideband on it, but I wanted to seek advice before I go returning cables back and forth. I'm at a loss here. Thanks in advance for the help.