How to check mdadm software RAID array, if the e.g. the swap file is on it?

Question

I am on Linux Mint 18.1 with 4.8 kernel.

Question is: How to check (mdadm) software RAID array, if the e.g. the swap file is on it?

I need the correct procedure before and after calling the checkarray script to define proper alias.

Answer 1

In this example the array is called md0 and it's mounted in /raid1.

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Check array alias:

1. Supposing a swap file is located on the array, we need to turn it off first. If that is the only swap area on the system, we can do:

   sudo swapoff --all
   

2. The array needs to be unmounted in order for it to be checked properly:

   sudo umount /raid1
   

3. After this preparation took place, we may call the checkarray script, I chose fast priority, but you may choose any priority option:

   sudo /usr/share/mdadm/checkarray --fast /dev/md0
   

4. If you wish to watch the progress of the array check every second:

   watch -n 1 cat /proc/mdstat
   

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So the complete bash check array alias located e.g. in your personal .bash_aliases file would look something like:

alias checkarray='sudo swapoff --all && \
                  sudo umount /raid1 && \
                  sudo /usr/share/mdadm/checkarray --fast /dev/md0 && \
                  watch -n 1 cat /proc/mdstat'

Make sure you close all open files on the array before calling it.

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After-Check array alias:

I think no further comments needed:

alias checkarray-after='sudo mount /dev/md0 /raid1 && \
                        sudo swapon --all'