Other Potential Problems
Topic | Information |
DOS ASPI | MEGASPI.SYS, the MegaRAID DOS ASPI manager, uses |
| 6 KB of system memory once it is loaded. |
At this time, copied CDs are not accessible from DOS even | |
under DOS | after loading MEGASPI.SYS and AMICDROM.SYS. |
Physical Drive Errors | To display the MegaRAID Manager Media Error and Other |
| Error options, press <F2> after selecting a physical drive |
| under the Physical Drive menu, selected from the Objects |
| menu. A Media Error is an error that occurred while |
| actually transferring data. An Other Error is an error that |
| occurs at the hardware level because of a device failure, |
| poor cabling, bad termination, signal loss, etc. |
Virtual Sizing | The Virtual Sizing option enables RAID expansion. Virtual |
| Sizing must be enabled to increase the size of a logical |
| drive or add a physical drive to an existing logical drive. |
| Run MegaRAID Manager by pressing <Ctrl> <M> to |
| enable Virtual Sizing. Select the Objects menu, then select |
| the Logical Drive menu. Select View/Update Parameters. |
| Set Virtual Sizing to Enabled. |
BSD Unix | We do not provide a driver for BSDI Unix. MegaRAID |
| Express 500 does not support BSDI Unix. |
Multiple LUNs | MegaRAID Express 500 supports one LUN per each target |
| ID. No multiple LUN devices are supported. |
MegaRAID Express | The Maximum MegaRAID Express 500 power |
Power Requirements | requirements are 15 watts at 5V and 3 Amps. |
SCSI Bus | The ANSI specification dictates the following: |
Requirements | The maximum signal path length between terminators is 3 |
| |
| meters when using up to 4 maximum capacitance (25 pF) |
| devices and 1.5 meters when using more than 4 devices. |
| SCSI devices should be uniformly spaced between |
| terminators, with the end devices located as close as |
| possible to the terminators. |
| The characteristic impedance of the cable should be 90 +/- |
| 6 ohms for the /REQ and /ACK signals and 90 +/- 10 ohms |
| for all other signals. |
| The stub length(the distance from the controller's external |
| connector to the mainline SCSI bus) shall not exceed.1m |
| (approximately 4 inches). |
| The spacing of devices on the mainline SCSI bus should be |
| at least three times the stub length. |
| All signal lines shall be terminated once at both ends of the |
| bus powered by the TERMPWR line. |
Chapter 8 Troubleshooting | 105 |