2120S Raid Controller and DAT Tape?

[Jay Daniels]

On Sun, Apr 11, 2004 at 10:49:23PM -0500, Jeff Vian wrote:
> Jay Daniels wrote:
> 
> >On Sun, Apr 11, 2004 at 06:11:39PM +0200, Alexander Dalloz wrote:
> > 
> >
> >>Am So, den 11.04.2004 schrieb Jay Daniels um 17:09:
> >>
> >>   
> >>
> >>>I have a scsi raid controller 2120S with 4 scsi ibm 320 scsi drives
> >>>installed and working.  The 2120S is the only raid card on the box and
> >>>it also has a some type of hot swap card which all the drives are
> >>>connected.
> >>>
> >>>So how do I connect my new scsi DAT tape drive to this box?  Will I
> >>>need another raid card to run the scsi DAT tape drive???
> >>>     
> >>>
> >>I do not know the SCSI RAID controller. If it can independent from it's
> >>RAID functionality - and that is an important fact too, if your SCSI DAT
> >>tape drive is LVD too like the hard drives - be used for a single SCSI
> >>device, then you can plug in the DAT drive too. If the controller is
> >>only a RAID controller, or no separate SCSI connector is free, or your
> >>DAT tape drive is not LVD and thus would switch down the whole SCSI bus
> >>to non-LVD speed then it is need that you build in an own SCSI
> >>controller card for the tape drive. Of course that card has not to be a
> >>RAID controller too. Check which SCSI type the tape drive is and then
> >>get a controller card serving that SCSI tape with an outside connector.
> >>
> >>   
> >>
> >>>jay
> >>>     
> >>>
> >>Alexander
> >>   
> >>
> >
> >It's a Seagate Scorpion 40 DDS-4 "internal" drive.
> >
> >The Scorpion 40 supports the following SCSI interfaces:
> >68-pin Ultra 2 SCSI (LVD)
> >68-pin SCSI Wide (single-ended)
> >50-pin SCSI-2(requires 68- to 60-pin adaptor)
> >
> >I currently have my hard drives on an adaptec 2120S with hot swap
> >card.  The cable runs from the raid adaptor to the card.  The 2120s
> >card is a 64bit pci card.
> >
> >Also, I use scsi 5 raid array and don't know if that would require me
> >to install the tape drive on another scsi adaptor.
> > 
> >
> According to the Adaptec site the 2120S is raid5 hardware controller, 
> ultra 320.
> 
> You cannot attach a non-raid device such as a tape drive to this adapter.
> 
> You will have to have an adapter appropriate for the tape drive to 
> connect it.
> 
> >So is the 2120S considered an Ultra 2 SCSI (LVD)?  Do I need to go
> >into the adaptec setup of the 2120s to setup the tape drive?
> > 
> >
> No, and No.
> 
> >I do not want to purchase another expensive scsi card if possible. The
> >server will hold up to 7 320 scsi drives but currently I only have 4
> >and don't think I will add any more hotswap hard drives.
> > 
> >
> You have no choice.  Hardware raid controllers do not support non-raid 
> devices.
> 
> >I spent a lot of money for this tape drive and want the best
> >performance!  Oh, I also need a ribbon cable - no cable in the box, or
> >do I really need a cable?  The cable from the 2120s to the hot swap
> >card is long and has extra connections!
> >
> > 
> >
> You need to check the specifications on the tape drive.
> Is it scsi2 UW or scsi2 UW fast.
> 
> I suspect from the info you give and what I know of most DDS4 tape 
> drives it is scsi2 UW and not likely faster.
> 
> If you want an inexpensive scsi adapter, an adaptec AHA2940UW or similar 
> would work well.
> You will need a cable to attach to the drive, and if the drive/enclosure 
> is not self terminating you will also need a terminator for the end near 
> the tape drive.
> All scsi buses must be terminated at both ends.  The adapter will 
> usually be one end, the furthest device is the other end.
> jeff

Jeff, I have an old Adaptec AHA2940UW but I have only one more 32 bit
pci slot and no AGP slot.  I was hoping to use that slot to install a
better video adaptor than the built in Rage XL.

Good to know, Hardware raid controllers do not support non-raid storage
devices.  I had a feeling this was true since I called a Linux vendor
years ago and the tech said that if I wanted a scsi scanner interface
that I need to install another scsi adaptor for the scanner.


jay