• Bare Metal Server

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  6. Overview


What Is an Image?

An image is a template of the BMS running environment. It contains an OS and runtime environment, and also some pre-installed applications. An image file is equivalent to a copy file that contains all data in the system disk.

Image Types

Images can be classified into public images, private images, and shared images based on the image source.

Table 1 Image types

Image Type


Public image

A public image is a standard, widely used image. It contains an OS and preinstalled public applications or services and is available to all users.

Private image

A private image contains an OS, pre-installed public applications, and a user's private applications. It is visible only to the user who creates it. Using a private image to create BMSs removes the need to configure multiple BMSs repeatedly.

Shared image

This is a private image shared by another user.

Public Image

Public images are provided by the system. These images are adaptable to BMS compatibility with necessary initial plug-ins and are available to all users. Most mainstream OSs are included. Available public images vary depending on the BMS flavor.


  • OS types: Linux and Windows OSs that are updated and maintained periodically
  • Supported software: Public images integrate some plug-ins on which BMS storage, networks, and basic functions depend.

    These plug-ins are necessary for BMSs to run properly. Do not delete or modify any of them. Otherwise, your BMS basic functions will be affected.

    Table 2 Supported software




    Cloud-Init is an open-source cloud initialization program, which initializes specified customized configurations, such as the host name, key, and user data, of a newly created BMS.

    bms-network-config network configuration plug-in

    This plug-in is used to automatically configure BMS networks during BMS provisioning and restore the BMS network when the network is interrupted due to misoperations.

    SDI iNIC frontend driver plug-in

    This plug-in is installed on the image so that BMSs can have EVS disks attached and can start from EVS disks, which enables quick BMS provisioning.

  • Compatibility: Public images are compatible with server hardware.
  • Security: Public images are highly stable and licensed.
  • Restrictions: There is no restrictions on using public images.

Private Image

A private image contains an OS, preinstalled public applications, and a user's private applications. Using a private image to create BMSs frees you from configuring BMSs repeatedly.


  • Compatibility: Private images only adapt to servers of the same model as the private images and may fail to deploy BMSs of other models.
  • Supported functions: You can create and delete private images, as well as create BMSs and reinstall the BMS OS using private images.
  • Restrictions: You can create a maximum of 500 private images.

Public Images

Private images refer to images shared by other tenants with you.

Application Scenarios

  • Deploying software environments in a batch

    Use a BMS with an OS, partitions, and software to create a private image, and then use the image to create BMSs in a batch. The created BMSs have the same configuration as the source BMS.

  • Backing up a BMS

    Create an image from a BMS to back up the BMS. If the software of the BMS becomes faulty, you can use the image to restore the BMS.