About mysql : How-can-i-use-the-mounted-storage-from-devmd3-to-devmd2-can-i-add-stage-space-from-md3-to-md2

Filesystem      Size  Used Avail Use% Mounted on
udev             63G     0   63G   0% /dev
tmpfs            13G  1.1M   13G   1% /run
/dev/md2        2.0T  591G  1.3T  32% /
tmpfs            63G     0   63G   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs            63G     0   63G   0% /sys/fs/cgroup
/dev/md1        485M   82M  378M  18% /boot
/dev/md3        1.5T   28K  1.5T   1% /home
tmpfs            13G     0   13G   0% /run/user/0