Move or Relocate /var Directory to a New Partition in Linux
sudo init 1
fdisk /dev/sdb
Command (m for help): p
Command (m for help): g
Command (m for help): n, Enter, Enter, Enter
Command (m for help): w
mkfs.ext4 /dev/sdb1
mkdir -p /media/newvar
cp -apx /var/* /media/newvar
mv /var /var.old
mkdir /var
blkid >> /etc/fstab
nano /etc/fstab
reboot
#or
systemctl reboot