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Redundant Array of Inexpensive Disks (RAID)¶

https://docs.kernel.org/admin-guide/md.html
https://en.wikipedia.org/wiki/RAID

in this section

* configure linux to boot with a degraded array

* create a raid5 array

* create raid config file

* create raid0 array

* recover raid array on an external disk

* remove a raid array

* replace a raid1 array drive

* speed up raid array sync