3.2.18. /proc/mdstat

3.2.18. /proc/mdstat

This file contains the current information for multiple-disk, RAID configurations. If the system does not contain such a configuration, then /proc/mdstat looks similar to the following:

Personalities :  read_ahead not set unused devices: <none>

This file remains in the same state as seen above unless a software RAID or md device is present. In that case, view /proc/mdstat to find the current status of mdX RAID devices.

The /proc/mdstat file below shows a system with its md0 configured as a RAID 1 device, while it is currently re-syncing the disks:

Personalities : [linear] [raid1] read_ahead 1024 sectors 
md0: active raid1 sda2[1] sdb2[0] 9940 blocks [2/2] [UU] resync=1% finish=12.3min algorithm 2 [3/3] [UUU] 
unused devices: <none>

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