ubuntu@ip-172-31-39-166:~$ grep ^/dev/xvdd /etc/mtab
/dev/xvdd1 /mnt ext4 rw,relatime 0 0
 
ubuntu@ip-172-31-39-166:~$ grep ^/dev/xvdd /etc/mtab | sudo tee -a /etc/fstab
 
ubuntu@ip-172-31-39-166:~$ cat /etc/fstab
LABEL=cloudimg-rootfs  /       ext4  discard,commit=30,errors=remount-ro  0 1
LABEL=BOOT             /boot   ext4  defaults                             0 2
LABEL=UEFI             /boot/efi    vfat    umask=0077                    0 1
/dev/xvdd1             /mnt    ext4  rw,relatime                          0 0
