So if I understand Kelly correctly, I can have 1 - 5912 going to 4 lto4 hh drives running at 3Gb/sec per drive and not oversaturate the bus or adapter when all four drives are active. Do you know anyone actually running with this configuration with a p570?
Kelly Lipp <[EMAIL PROTECTED] COM> To Sent by: "ADSM: ADSM-L@VM.MARIST.EDU Dist Stor cc Manager" <[EMAIL PROTECTED] Subject .EDU> Re: [ADSM-L] IBM 3200 Tape Library SAS adapters 11/20/2008 09:57 AM Please respond to "ADSM: Dist Stor Manager" <[EMAIL PROTECTED] .EDU> SAS is very different from SCSI so all bets are off when comparing the two. An x4 4 lane SAS adapter will support 4 SAS drives. You will need an interposer plugged into the SAS card which splits the four lanes onto four cables. Then plug each drives cable into the interposer and you are completely fanned out. One lane per drive (each lane is 3Gb/sec transfer rate, well fast enough for one LTO4 tape drive). Kelly Lipp CTO STORServer, Inc. 485-B Elkton Drive Colorado Springs, CO 80907 719-266-8777 www.storserver.com -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of Mark Stapleton Sent: Thursday, November 20, 2008 10:53 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: [ADSM-L] IBM 3200 Tape Library SAS adapters No docs, but you want as many ports as possible for maximum throughput. Officially, you can put three drives per HBA port (through a switch, not Y cables). I tell customers that a maximum of two drives per HBA port will make them a LOT happier; three LTO4 drives could saturate the connection, and that's a bad thing with tape. -- Mark Stapleton ([EMAIL PROTECTED]) CDW Berbee System engineer 7145 Boone Avenue North, Suite 140 Brooklyn Park MN 55428-1511 763-592-5963 www.berbee.com > -----Original Message----- > From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf > Of Larry Peifer > Sent: Thursday, November 20, 2008 12:49 PM > To: ADSM-L@VM.MARIST.EDU > Subject: [ADSM-L] IBM 3200 Tape Library SAS adapters > > We are in the process of purchasing an IBM 3200 Tape Library with 4 - > LTO4 > half-height SAS drives. Our IBM sales rep and tech support rep are > telling > us that we need 4 - 5912 HBAs, one for each drive, to support this > configuration in our IBM 9117-MMA (p570) host. > > From our review of the tech specs it looks like the 5912 Adapter (PCI-X > DDR > Dual -x4 SAS Adapter) should be able to support all four SAS tape > drives > from one card using 2- YO cables in the same way it can support 4 disk > drives. Can anyone point us to someone or some docs that can give us > more > information. > > Larry Peifer > San Onofre Nuclear Generating Station > AIX System Admin > TSM system Admin