Promise Technology VTRAK 15100, User Manual

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VTrak 15100 User Manual
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Connection Problems
When you install your Promise product following the instructions in the Quick
Start Guide and User Manual , you should have little trouble getting your
equipment to work the first time. But connection problems can arise that are not
the User's or Installer's fault. Every conceivable problem cannot be covered in
the documentation but some guidelines could be helpful.
Connection problems cause a majority of failures in almost any electrical system.
While the installation of the cables and components was correct, they don't
function properly, or at all, because:
•
A connector is dirty or corroded
• A connector is loose or damaged
• A cable looks OK outside but has an open circuit inside
• The wrong cable was used
Promise products ship with a full set of new cables and terminators, as required
for each specific product. Be sure to use these components because: 1.) They
are the proper ones for your RAID subsystem, 2.) They are in brand-new
condition, and 3.) You paid for them with the purchase of your Promise product.
SCSI Connections
Products like the Promise UltraTrak, use In-Band SCSI technology to pass
command and management information between the RAID subsystem and Host/
RAID PC. The Promise VTrak has embedded technology, and uses a network
connection to pass command and management information. With both of these
products, data is transmitted via the SCSI bus.
SCSI connections are both physical (outside) and electrical (inside). You can see
a physical connection, you can clean it or try a different cable on it. Electrical
connections are made by firmware and software, such as when you set the SCSI
IDs or addresses. SCSI chains are completely intolerant of ID conflicts. If you
have a conflict, the devices on your SCSI chain will not work correctly until it is
resolved. The Promise UltraTrak and VTrak RAID subsystems make use of
Target IDs and LUNs but in different ways.
The VTrak RAID subsystem is sensitive to the presence of other devices on the
SCSI chain. Promise recommends that you connect no other devices to the SCSI
chain with a VTrak, except for an other VTrak.