Check For Multiple Scsi Ids - ADIC Scalar 100 User Manual

• The SNC has internal terminators on its SCSI channels.
• The terminators can be disabled from the ADIC Management Console.
• Using the Controls > SCSI Channel menu, verify that termination has not
inadvertently been disabled.
2. The last physical device on a chain of SCSI devices needs to be terminated.
• If the end device has internal termination, be sure it is enabled.
• Otherwise check that an external terminator is attached to the device.
• A Differential (DE) terminator on a Single Ended (SE) bus or an SE terminator on a
DE bus will cause the bus to be unusable.
• Verify the type of terminators for each SCSI channel.
3. Excessive termination: Check that all SCSI devices other than the end devices have
internal termination disabled.
4. If SCSI termination is OK, go to "Check for Multiple SCSI IDs" below.
5. If you powered the Scalar 100 down in order to correct a SCSI termination problem,
turn it back on.
• After the Scalar 100 and the SNC finish booting, enter the scsiShow command
from the service terminal. Note that the Scalar 100 takes longer to complete its boot
than does the SNC.
• Compare the list of attached devices with the physical devices.
• If not all of the physical devices are shown, go to "Check for Multiple SCSI IDs"
below.
• Otherwise, go to "SCSI Health Check" on page 138.

Check for Multiple SCSI IDs

If two or more devices on the same SCSI channel are configured at the same SCSI ID,
only one of those devices will be seen by the SNC. Data transfers to that device will be
unreliable.
1. Write down the SCSI IDs of all devices connected to each SCSI channel.
2. Check that only one device is set to each ID for each SCSI channel.
page 136
Attention: If in this procedure you determine that you need to correct any
SCSI IDs, all I/O to the SNC must be stopped and the Scalar 100 must be
turned off.
Check for Multiple SCSI IDs