148:(as opposed to an "off-line" repair, during which the system is unavailable to users). Many RAID configurations feature spare disks that are already installed and can be automatically added to the array as needed; when this happens, the array may or may not go into degraded mode until the spare is rebuilt, but in any case should not be in degraded mode after the spare is rebuilt. If no spares are available, the array will remain in degraded mode until a spare disk is added, or the array is reconfigured (if that is possible for the configuration in question).
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https://raid.wiki.kernel.org/index.php/Write-intent_bitmap
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403:Oracle ZFS
380:Interfaces
370:Throughput
353:Parity bit
321:Principles
165:References
99:April 2018
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241:Redundant
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