• Bare Metal Server

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This document describes how to call the APIs of Bare Metal Server (BMS) to use the functions of the service. This chapter describes the concepts related to BMS to help you quickly understand the service.


A BMS is a physical server dedicated for individual tenants. It provides remarkable computing performance and stability for running key applications. The BMS service can be used in conjunction with other cloud services, such as Virtual Private Cloud (VPC), so that you can enjoy consistent and stable performance of server hosting as well as the high scalability of cloud resources.

Basic Concepts

  • Availability Zone

    An availability zone (AZ) is a physical location where resources use independent power supply and networks within a region. An AZ is insulated from failures in other AZs and provides inexpensive, low-latency network connectivity to other AZs in the same region. A region can have more than one AZ. AZs are physically isolated but interconnected through an internal network.

  • Project

    Projects are used to group and isolate OpenStack resources (computing resources, storage resources, and network resources). A project can be a department or a project team.

    A tenant can create multiple projects.

  • Elastic Volume Service (EVS)

    The EVS service offers scalable block storage for BMSs. With high reliability, high performance, and rich specifications, EVS disks can be used for distributed file systems, development and test environments, data warehouse applications, and high-performance computing (HPC) scenarios to meet diverse service requirements.

  • Virtual Private Cloud (VPC)

    A VPC provides you with a logically isolated network environment for BMSs. You can create virtual networks in a VPC. You can also create security groups and VPNs, configure IP address segments, and specify bandwidth sizes in your VPC. With a VPC, you can manage and configure internal networks and change network configurations, simplifying network management. You can also customize access rules to control BMS access within a security group and across different security groups to enhance BMS security.

  • User-defined VLAN

    You can use the Ethernet NICs (10GE defined in BMS specifications) not used by the system to configure a user-defined VLAN. The QinQ technology is used to isolate networks and provide additional physical planes and bandwidths. You can allocate VLAN subnets to isolate traffic in various scenarios including SAP HANA and VMware. User-defined VLAN NICs are in pairs. You can configure NIC bonding to achieve high availability. User-defined VLANs in different AZs cannot communicate.

  • IB network

    The IB network features low latency and high bandwidth and is used in a number of High Performance Computing (HPC) projects. It uses the 100 Gbit/s Mellanox IB NIC, dedicated IB switch, and controller software UFM to enable network communication and management, and uses the Partition Key to isolate IB networks of different tenants (similar to the VLAN in the Ethernet).

  • Image

    An image must contain an OS and can also contain application software (such as database software) and software configuration. An image is a BMS template.

    Images can be public or private. Public images are provided by the system by default, and private images are manually created by users. You can apply for a BMS using a public or private image. You can also create a private image using an existing BMS or external image. This provides you with a simple way to create BMSs that comply with your service requirements.