Configure Minimum Rebuild Rates Per Node

Set a node minimum array rebuild rate for single or multiple drive failures

Before performing this operation, select the target nodes, as described in the Use Node Filters topic.
Use the Minimum Rebuild Rates feature from the Node Control tab to set node minimum array rebuild rates (speed) for single or multiple drive failures. For the selected nodes only, this setting will override the global minimum rebuild rate that is set on the Configure tab.
Note: It is recommended that minimum rebuild rates not be lower than 1,000 KB/sec or greater than 200,000 KB/sec. Values higher than 200,000 KB/sec are not likely to provide faster overall rebuild time, but I/O performance will be impacted. Values lower than 1,000 are not likely to show an increase in I/O performance during rebuilds. A value of 0 is permitted, but this will halt rebuild activity, which increases the risk to stored data.

Single drive failures are serious but not as critical as multiple drive failures, since an array being rebuilt because of a single drive failure could sustain another drive failure and remain operational. Therefore, the minimum rebuild rate setting for single-drive failures should typically be lower than for multiple-drive failures.

Multiple-drive failures are critical conditions and need as much speed as possible allocated to the rebuild process. This helps minimize the exposure of another drive failing while the array is being rebuilt. For this reason, we recommend setting the minimum rebuild rate for multiple drive failures to the maximum value of 200,000 KB/sec.

To set the rebuild policy for individual nodes:

  1. Navigate to the Node Control tab, and then select the target nodes that need the minimum rebuild rate changed.
  2. Click the Selected Nodes button, and then select the Minimum Rebuild Rates... option from the menu.
    While the rebuild rate can be set for all nodes, it only applies to nodes that have RAID arrays.
  3. Enter minimum rebuild rates (KB/sec) for single drive failures in the Single drive failure reconstruction rate field and in the Single drive failure reblance rate field.
    The default setting is 50,000 KB/sec.
  4. Enter the minimum rebuild rate for multiple drive failures in the Multiple drive failures (all rates) field.
    The default setting is 80,000 KB/sec.
  5. To save the changes, click the Apply button. To cancel the operation, click the Cancel button.
    The GUI does not correctly validate entries for the minimum rebuild rates, which may result in an error when very large numbers are entered.