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Elastic Compute Service:Instructions for purchase

Last Updated:Sep 20, 2023

This topic describes the information that you must familiarize yourself with before you purchase Elastic Compute Service (ECS) instances.

Resource upgrades

For information about how to upgrade ECS instances, see Overview of instance configuration changes. Before you upgrade ECS instances, take note of the following items:

  • ECS instances, except those that use local storage, can have their CPU and memory resources scaled and their bandwidths upgraded while the instances are running. After the new configurations of instances take effect, you can downgrade the configurations of the instances.

  • In most cases, up to 16 data disks can be attached to an ECS instance. You cannot shrink a data disk after the data disk is extended.

  • The bandwidth of each ECS instance is measured in Mbit/s and can range from 0 Mbit/s to 200 Mbit/s. You can modify the bandwidth or change the billing method for network usage.

References

The following topics describe the basic terms of ECS and how to use ECS:

  • For information about the terms and services related to ECS, What is ECS?

  • For information about how to select ECS instance families and types, see Overview of instance families.

  • For information about how to select operating systems for instances, see Select an image.

  • For information about the performance of block storage devices, see Block storage performance.

  • For information about the usage notes on ECS instances, see Usage notes.

  • For information about the characteristics of pay-as-you-go resources, see Pay-as-you-go.

  • For information about the characteristics of subscription resources, see Subscription.

  • For information about the limits that apply to ECS, see Limits.

  • If you want to select instance types based on the benchmark data about their compute performance, contact your Service Manager.