How to add a new HDD in ubuntu 16.04

It depends how you intend to use it. I have an extra hard disk drive with a data partition, where I keep my own data (instead of in the home directory). This makes it very straightforward to separate the backup of the system from the backup of my own data (documents, own program code, pictures, music, video clips etc).

It is not necessary to have this partition in fstab, but I have it there, because it is convenient. It will always be mounted (unless I unmount it). Earlier I dual booted with Windows, so I had the NTFS file system, but now I have an ext file system since several years. It has an ext3 file system, but if I would make it now, I would use the ext4 file system. This is the corresponding line in fstab:

UUID=d3f3e5a3-3deb-4e43-8e1a-c2f0de792f90 /media/multimed-2     ext3    defaults 0       2

People recommend to create a mountpoint in the /mnt directory, for example

/mnt/data (instead of /media/multimed-2, which I use for historical reasons).

-o-

Another common way to use a second drive is the create a home partition, copy (move) the content of your home directory to it and mount it as /home (in fstab).

-o-

Edit: I suggest that you use gparted to create one or more partitions with suitable file systems.

Try this:

Open a terminal,

Press Ctrl+Alt+T

Run it:

exec sudo -i
apt-get update
apt-get dist-upgrade
apt-get install --reinstall gparted

In gparted select the drive Disk /dev/sda: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors

Creates a new msdos partition table.

In unallocated space, create an ext4 file system partition.

Apply the changes and close gparted to continue running:

blkid /dev/sda1

This command will give you a output similar to this:

/dev/sda1: UUID="1532e85b-0337-412d-9644-ef6ad282efdb" TYPE="ext4" PARTUUID="ab6eab6e-01"

Write down the UUID, and continue running:

mkdir /media/data  *--- Change this directory as you wish*
nano etc/fstab

In the open file add these lines:

# /media/data was on /dev/sda1
UUID=1532e85b-0337-412d-9644-ef6ad282efdb /boot           ext4    defaults        0       2

Ctrl+O Save file

Ctrl+X Close nano

Continue running:

mount -a
chmod -Rf 777 /media/data
exit

This is all. Your disk should be mounted and ready to use.

Remember to change /media/data by as you wish