AMCC 720-0138-00 manual Setting Continue on Source Error During Rebuild

Setting Unit Policies

Setting Continue on Source Error During Rebuild

The Continue on Source Error During Rebuild policy is available for units which are redundant. (For units which are not redundant, this option is not shown on the screen.) When this policy is set, ECC (Error Correcting Code) errors are ignored when they are encountered during a rebuild. (ECC errors are typically defects that have been detected in the drive since initialization.) When this policy is not set, if a unit is rebuilding, the rebuild will abort when it encounters an ECC error and the unit will be set back to Degraded.

Since enabling this policy could result in the loss of some source data in the event of source errors, the default is to not enable this policy. Select this option only if you want to ensure that a rebuild will complete successfully without manual intervention. If the rebuild fails and Continue on Source Error During Rebuild is not selected, then you have the option to start another rebuild manually. After completing a rebuild with this policy enabled, it is recommended that you execute a file system check when the rebuild completes. On Mac OS X, you can do this using the First Aid tab in the Disk Utility—select the disk on the left and then click Verify Disk. If verification encounters problems, you can then use the Repair Disk option on the same screen.

To set the Continue on Source Error During Rebuild policy in 3DM

1Choose Management > Controller Settings from the menu bar in 3DM.

2In the Unit Policies section of the Controller Settings page, check the boxes to select the policies you want to be in effect for each unit

The page refreshes, and a message at the top confirms the change you have made.

Enabling and Disabling Queuing for a Unit

Some drives support NCQ (Native Command Queuing), a feature that can result in increased performance for applications that require a lot of random access of data (usually server-type applications). This is accomplished by causing command reordering to be done on the drive.

In order to make use of NCQ, the feature must be enabled at both the drive and the controller.

You can see whether NCQ is supported and enabled for a particular drive in the Drive Details window. For details, see “Drive Details window” on page 92.

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