Scenarios and Disk Partitions

If you have added a data disk during ECS creation, you must initialize the data disk after logging in to the ECS.

Scenarios

After a disk is attached to a server, you need to log in to the server to initialize the disk, that is, format the disk. You must initialize a disk before accessing it.

System disk
A system disk does not require manual initialization because it is automatically created and initialized upon server creation. The default partition style is master boot record (MBR).
Data disk
- If a data disk is created along with a server, it will be automatically attached to the server.
- If a data disk is created separately, you need to manually attach it to a server.
In both cases, you must initialize the data disk before using it. Choose an appropriate partition style based on your service plan.

Partitioning Operation Guide

Table 1 lists the common disk partition styles. In Linux, different disk partition styles require different partitioning tools.

**Table 1** Disk partition styles
Disk Partition Style	Maximum Disk Capacity Supported	Maximum Number of Partitions Supported	Linux Partitioning Tool
Master Boot Record (MBR)	2 TiB	4 primary partitions 3 primary partitions and 1 extended partition With MBR, you can create several primary partitions and one extended partition. The extended partition must be divided into logical partitions before use. For example, if 6 partitions need to be created, you can create them in the following two ways: 3 primary partitions and 1 extended partition, with the extended partition divided into 3 logical partitions 1 primary partition and 1 extended partition, with the extended partition divided into 5 logical partitions	fdisk parted
GUID Partition Table (GPT)	18 EiB 1 EiB = 1048576 TiB	Unlimited Disk partitions created using GPT are not categorized.	parted