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Elastic Compute Service

Partitioning and formatting a volume

Overview

After creating a volume and attaching it to an ECS instance, you must partition and format the volume before you can use it. This topic provides notes and use cases for partitioning and formatting volumes.

Notes

Partitioning and formatting operations only apply to brand new volumes. If a volume contains data when it is created, partitioning and formatting may result in data loss.

Only data volumes support partitioning. System volumes do not support partitioning.

When you create an instance, a system volume is automatically created, partitioned, and formatted with Master Boot Record (MBR). You do not need to partition or format it yourself. Using third-party tools to partition the system volume can cause system crashes and data loss. You can only extend or add partitions after expanding the capacity of the system volume.

Use cases

The entire volume appears as one partition: We recommend creating a file system directly on the raw device instead of creating partitions. For more information, see Creating a file system on a raw device.

The entire volume appears as multiple logical partitions (i.e., multiple logical drives): First, partition the volume, and then create a file system on each partition.

Partitioning scheme	Partition size	Number of partitions	Partitioning tool	Related documentation
MBR (Master Boot Record)	Supports partitions ≤ 2 TiB	You can create up to four primary partitions or three primary partitions and one extended partition. You can create multiple logical partitions within an extended partition.	Windows: Disk Management	Partitioning and formatting a volume (≤ 2 TiB) - Windows
MBR (Master Boot Record)	Supports partitions ≤ 2 TiB				Linux: fdisk and parted	Partitioning and formatting a volume (≤ 2 TiB) - Linux
GPT (Globally Unique Identifier Partition Table)	Supports partitions of any size (no 2 TiB limit)	Windows: 128 Linux: Unlimited	Windows: Disk Management	Partitioning and formatting a volume (> 2 TiB) - Windows
GPT (Globally Unique Identifier Partition Table)	Supports partitions of any size (no 2 TiB limit)	Windows: 128 Linux: Unlimited			Linux: parted	Partitioning and formatting a volume (> 2 TiB) - Linux

Last updated: 2026.04.29 14:25:49