Hardware Installation
2.5Configurable Disk Drive SCSI Parameters
When a SCSI hard disk drive is initialized the first time by the RAID controller, its SCSI parameters are automatically set to their optimal settings. Most settings are set automatically and can not be configured manually. To view or configure disk drive SCSI parameters from the Storage Console, choose Advanced Setup Æ Configure Physical Devices Æ Select Physical Drive Æ SCSI Parameter/Initialize.
Table 2-1. Configurable Disk Drive SCSI Parameters
Parameter | Setting/ | Configuration | Description | |
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Synch. | Enabled / | Automatic | This setting when enabled allows the controller to | |
Transfer | Disabled | operate in synchronous transfer mode | ||
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| Allows for the setting of the speed for the SCSI | |
Synch. | Speed |
| hard disks (up to 320 MB/sec for U320 drives). | |
Automatic | No matter the setting, the SCSI bus will negotiate | |||
Transfer Rate | (MB/sec) | the fastest speed up to this setting. Lowering the | ||
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| setting will force the disk drive to transfer at the | |
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| lower speed. | |
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| Enabled / |
| Enabling this setting allows for the disk drive to | |
Disconnect | Automatic | disconnect from the SCSI bus when it’s not | ||
Disabled | participating in a transfer. This allows for optimal | |||
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| bus utilization by all devices on the bus. | |
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Tagged |
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| When enabled, this feature allows the SCSI disk | |
On / Off | Automatic | drive to execute more than one command at a | ||
Queues | ||||
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| time. | ||
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Disk Read |
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| For performance reasons, the Read Ahead and | |
and Write | On / Off | Configurable | Write cache of the hard disk drives should always | |
Cache |
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| be on. This is the default setting. | |
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2.6Configurable I/O Controller SCSI Parameters
When the controller starts up, its SCSI parameters are automatically set to their optimal settings. Manual configuration is not required. However, you can customize I/O SCSI parameters for each channel on the controller by using the Storage Console menu Advanced Setup > Configure Controller > Controller Settings.
Table 2-2. Configurable I/O Controller SCSI Parameters
Parameter | Setting/Value | Description |
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| When this is set to On, Domain validation allows for a |
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| cyclical check of the correct data transfer at a given rate for |
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| the respective channel. |
Domain Validation | On / Off | For ultra320, the SRCMRU controller supports Basic, |
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| Enhanced, and Margined Domain Validation. For ultra160, |
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| the SRCMRU controller supports Basic and Enhanced |
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| Domain Validation. |
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16 | Hardware Installation and User’s Guide |