Data Storage - Cannot Get AIT2 LVD To Work

Author

Cannot Get AIT2 LVD To Work

CHANGE USERNAME TO westes

2004-09-15, 9:55 am

Our AIT2 HVD drives have been among the most reliable we have used. We
have used them both with differential SCSI controllers as well as HVD fibre
bridges, both with great success. In our test lab, where we have two
permanent test servers that have Adaptec 39160 LVD host adapters, I cannot
get AIT2 LVD to work at all.

On one of the two servers, the AIT2 LVD drives come up but any operation
against them in Backup Exec 9.1 gives a CRC error. I have tried different
cables, different terminators, and different settings for speed on the
39160, all with no effect. On the second server, I cannot even get the
drive to be *seen* on the LVD chain. We tried AIT2 LVD drives in Scalar
100 libraries, Scalar 1000 libraries, and stand alone AIT2 LVD drives, all
with the same result. Finally, ready to pull my hair out, I even tried to
put them behind an ADIC SNC 5101 fibre bridge, which works fantastically
well with LTO1 and LTO2 LVD tape drives, but the effect was similar. As
soon as you start to work with the drives, they simply disapper from Windows
Device Manager.

At this point I have been threw different cables, terminators, servers, host
adapters, fibre bridges, and of course different AIT2 LVD drives, and I just
cannot find any combination that works reliably. Is there a trick to
using an AIT2 LVD drive, and is there a short list of host adapters that
work well with these?

--
Will
westes AT earthbroadcast.com

David Hawkins

2004-09-15, 8:48 pm

You are mixing High Voltage Differential interface ( HVD) and Low Voltage
Differential interface (LVD) parts this may result in damage to the drive
and or the host adapter.
If the AIT-2 is the SDX-510C then it has a HVD interface and needs a VHD
host adapter and terminators, the Adaptec AHA-2944UW is a HVD host.
The Adaptec 39160 is a LVD host and should be used with the SDX-500C and
LVD terminators.
( Yes both LVD and HVD use the same connectors !)

There is a bit on the Adaptec's pages about this at
http://www.adaptec.com/worldwide/su...fferential_SCSI

Dave

"CHANGE USERNAME TO westes" <DELETE_westes@earthbroadcast.com> wrote in
message news:KcSdnTC_XbDzZdrcRVn-qg@giganews.com...
> Our AIT2 HVD drives have been among the most reliable we have used. We
> have used them both with differential SCSI controllers as well as HVD
fibre
> bridges, both with great success. In our test lab, where we have two
> permanent test servers that have Adaptec 39160 LVD host adapters, I cannot
> get AIT2 LVD to work at all.
>
> On one of the two servers, the AIT2 LVD drives come up but any operation
> against them in Backup Exec 9.1 gives a CRC error. I have tried
different
> cables, different terminators, and different settings for speed on the
> 39160, all with no effect. On the second server, I cannot even get the
> drive to be *seen* on the LVD chain. We tried AIT2 LVD drives in Scalar
> 100 libraries, Scalar 1000 libraries, and stand alone AIT2 LVD drives, all
> with the same result. Finally, ready to pull my hair out, I even tried
to
> put them behind an ADIC SNC 5101 fibre bridge, which works fantastically
> well with LTO1 and LTO2 LVD tape drives, but the effect was similar. As
> soon as you start to work with the drives, they simply disapper from
Windows
> Device Manager.
>
> At this point I have been threw different cables, terminators, servers,
host
> adapters, fibre bridges, and of course different AIT2 LVD drives, and I
just
> cannot find any combination that works reliably. Is there a trick to
> using an AIT2 LVD drive, and is there a short list of host adapters that
> work well with these?
>
> --
> Will
> westes AT earthbroadcast.com
>
>

CHANGE USERNAME TO westes

2004-09-22, 10:29 pm

"David Hawkins" <david.j.hawkins@btinternet.com> wrote in message
news:ciao3a$9p1$1@hercules.btinternet.com...
> You are mixing High Voltage Differential interface ( HVD) and Low Voltage
> Differential interface (LVD) parts this may result in damage to the drive
> and or the host adapter.

Absolutely not. I am completely aware of the difference, and I would never
cross up the two. Three people have spent 20 hours on this now, and each
of us knows this lesson and cross checks each other on this specific issue.

I made the point about HVD because our early experience with AIT2 was
specific to that interface. But that was only background. We are
*migrating* *from* HVD to LVD, and of course each of these has a different
SCSI host adapter.

--
Will
westes AT earthbroadcast.com