/proc/mdstat Explained

Status of RAID devices

On a Linux system, the file /proc/mdstat contains information about the state of any software RAID arrays configured on the system. You can read this file using the cat command:

cat /proc/mdstat

This will display the status of any active RAID arrays, including the name of the array, the RAID level, and the status of the array (e.g., "active", "rebuilding", etc.). It will also show the names of the disks that are part of the array, along with any spare disks that may be present.

To determine if the disks in the RAID array are alright, you can look at the status of the array. If the array is "active", this means that it is functioning normally and all of the disks are working as expected. If the array is "degraded", this means that one or more disks have failed or are not functioning properly, and the array is running in a degraded state. In this case, you may need to replace the failed disks or repair the array to bring it back to a fully functioning state.

It's also a good idea to check the individual disk status using tools like smartctl, which can provide more detailed information about the health and status of the disks.