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At this point, we know which storage device is new—there's no doubt that in the 
preceding example, it's 
/dev/sdb
. We always need to make sure we don't attempt to 
format or repartition the wrong device, or we may lose data. In this case, we can see 
/dev/sdb
 has no partitions (and this volume wasn't present before I added it), so it's 
obvious which disk we'll want to be working with. Now we can create one or more 
partitions on it, to continue preparing it for use.
Creating a partition
To create an actual partition on this device, we'll use the 
fdisk
 command with 
sudo
, 
using the device's name as an option. In my case, I would execute the following to 
work with disk 
/dev/sdb
:
sudo fdisk /dev/sdb
Note that I didn't include a partition number here, as 
fdisk
 works with the disk 
directly (and we also have yet to create any partitions). In this section, I'm assuming 
you have a disk that has yet to be partitioned or one you won't mind wiping. When 
executed correctly, 
fdisk
 will show you an introductory message and give you a 
prompt:
Figure 9.4: Main prompt of fdisk
At this point, you can press 
m
 on your keyboard for a menu of possible commands 
you can execute. In this example, I'll walk you through the commands required to set 
up a new disk for the first time.

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Managing Storage Volumes
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Before we continue with creating a new partition, some discussion is required with 
regards to 
Master Boot Record
 (
MBR
) and 
GUID Partition Table
 (
GPT
) partition 
tables. When creating a partition table on a new disk, you'll have the option to set it 
up to use an MBR or GPT partition table. GPT is the newer standard, while MBR has 
been around for quite some time and is probably what you've been using if you've 
ever created partitions in the past.
With MBR partition tables, you have some limitations to consider. First, MBR only 
allows you to create up to four primary partitions. In addition, it also limits you to 
using somewhere around 2 TB of a disk. If the capacity of your disk is 2 TB or less, 
this won't be an issue. However, disks larger than 2 TB are becoming more and more 
common.
I'm sure it goes without saying, but be aware of the destructive 
possibilities of 
fdisk
. If you run 
fdisk
 against the wrong 
drive, irrecoverable data loss may result. It's common for an 
administrator to memorize utilities such as 
fdisk
 to the point 
where using it becomes muscle-memory. But always make 
sure that you take the time to ensure that you're running such 
commands against the appropriate disk.
You may see MBR referred to as DOS when referring to the older