$ df | egrep '/dev/md|File'
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/md0 49687632 13045168 34088764 28% /
/dev/md3 960249880 514337568 397064492 57% /a
/dev/md2 402626372 13579452 368524324 4% /home
$ mount | grep /dev/md
/dev/md0 on / type ext4 (rw,relatime,errors=remount-ro,data=ordered)
/dev/md3 on /a type ext4 (rw,relatime,data=ordered)
/dev/md2 on /home type ext4 (rw,relatime,data=ordered)
$ grep md2 /proc/mdstat
md2 : active raid1 sda3[0] sdb3[1]
$ sudo fdisk -l | grep '^Disk /dev/sd'
Disk /dev/sdb: 447.1 GiB, 480103981056 bytes, 937703088 sectors
Disk /dev/sda: 447.1 GiB, 480103981056 bytes, 937703088 sectors
Disk /dev/sdc: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
Disk /dev/sdd: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
$ df
Filesystem 1K-blocks Used Available Use% Mounted on
udev 8060648 0 8060648 0% /dev
tmpfs 1618832 2088 1616744 1% /run
/dev/md0 49687632 13045168 34088764 28% /
tmpfs 8094148 40092 8054056 1% /dev/shm
tmpfs 5120 4 5116 1% /run/lock
tmpfs 8094148 0 8094148 0% /sys/fs/cgroup
/dev/loop0 99456 99456 0 100% /snap/core/9289
/dev/loop1 96256 96256 0 100% /snap/core/9066
/dev/loop2 18304 18304 0 100% /snap/pdftk/9
/dev/md3 960249880 514337568 397064492 57% /a
/dev/md2 402626372 13579452 368524324 4% /home
tmpfs 1618828 16 1618812 1% /run/user/125
tmpfs 1618828 96 1618732 1% /run/user/1000
tmpfs 1618828 0 1618828 0% /run/user/0
$
