Date - 12/2006
Affected Product & Version - Netvault Backup All Versions
Affected Module & Version - N/A
OS Version - All
Application Information - N/A
Getting "Data Phase Error" when reading from or writing to media
NetVault will mark the tape "read only" or "bad", but the error is usually caused by a SCSI bus issue
1. Check Terminator - There is more than one kind of terminator (i.e. SE, LVD, HVD), you may have the wrong one, or your terminator might be bad.
2. Check SCSI Cables - Verify that all cables are seated properly on both ends, and that the pins are not bent. A cable might be bad, even if everything appears good.
3. Remove other devices from the SCSI bus. Other devices on the SCSI bus could have problems that affect the whole SCSI bus. An example of a common problem would be, one Single Ended device on the SCSI bus forcing the whole bus to go Single Ended.
4. Check cable length. Each type of SCSI bus has different cable limitations.
SE or Single Ended - 3 Meters
HVD or High Voltage Differential - 25 Meters
LVD or Low Voltage Differential - 12 Meters
If the SCSI cables inside devices and external cables exceed these limitations, you need to use shorter cables, or remove devices to shorten the total cable length. A library might have 1 or 2 meters of cable inside, so SE buses often run in to this problem.