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This section provides an introduction to Contrail Cloud and the Contrail Cloud reference architecture.

About This Reference Architecture

This reference architecture provides networking professionals with the concepts and tools needed to optimally architect a Contrail Cloud environment. The intended audience for this guide includes system integrators, infrastructure professionals, partners, and customers that are currently deploying or are considering deploying Contrail Cloud.

The architecture presented in this guide is intended for implementation with Contrail Cloud 13.1 and 13.2 environments.

Contrail Cloud Overview

Juniper Networks Contrail Cloud provides cloud service providers with a bundled solution to build cloud platform infrastructures. The Contrail Cloud bundle simplifies your cloud building journey by integrating multiple software components—Red Hat Openstack orchestration, Contrail Networking, Red Hat Ceph Storage, and Appformix—into a bundle with pre-configured files that is collectively installed on multiple devices using a single installation procedure.

The bundled Contrail Cloud package includes:

  • Red Hat OpenStack

  • Red Hat Ceph Storage

  • Juniper Networks Contrail Networking

  • Juniper Networks Contrail Command

  • Juniper Networks AppFormix

  • Pre-configured YAML files to simplify the initial configuration procedures, as well as script files to implement configuration changes.

All Contrail Cloud software components are downloaded from a Juniper Satellite site. You must send an email request to to obtain the credentials to access the Juniper Satellite site. See Deploying Contrail Cloud.

The remainder of this reference architecture assumes that the reader has a strong working knowledge of Contrail Cloud. For additional information on Contrail Cloud fundamentals, see the Contrail Cloud Product Information page and the Contrail Cloud TechLibrary page.

Reference Architecture Overview

This document provides a reference architecture for a Contrail Cloud 13.1 or 13.2 deployment. The reference architecture has been tested by Juniper Networks and is optimized for performance, scale, and resilience. It provides sample server and network device configurations as well as design guidance to provide in-depth insight on the configuration and design decisions made within Contrail Cloud architectures.

The main design characteristics of this reference architecture:

  • Three controller nodes that are installed in different racks for high availability.

  • A subnetting scheme that provides separate subnets per rack for tenant data, internal API, and storage traffic.

  • An IP Fabric that includes leaf devices dual-homed to spine devices while connecting to separate SDN gateway routers. The IP Fabric runs EVPN-VXLAN.

  • Separate NICs for tenant data and storage traffic.

This reference architecture includes sections that describe supported variations to the architecture. The supported variations include environments with a reduced number of physical interfaces and simplified networking setups. See Enhanced Resilience and Scale Variations and Reference Architecture Variations.

The following deployment scenarios are covered in this reference architecture:

  • large scale, high performance cloud deployments.

  • Deployments with compute nodes in any combination of kernel, DPDK, and SR-IOV modes.

  • Dual-homed compute nodes with separate and combined management, control/data, and storage networks.

In this document, configuration file fragments are provided that show how to configure the components of a Contrail Cloud environment to meet the specifications of the deployment architecture.

This document is intended to be used in conjunction with the Contrail Cloud Deployment Guide, which provides Contrail Cloud installation procedures.

Reference Architecture Scope

Contrail Cloud is a software package that arrives with detailed descriptions of how networking should be established on servers running in the topology and the options available for configuring the software running on the servers.

This reference architecture document provides details and recommendations for configuring Contrail Cloud beyond the initial server setup. This reference architecture also provides walkthroughs and advice related to optimizing the networking between servers and the fabric in a Contrail Cloud environment.

Figure 1 visually provides the high-level overview of a typical cloud environment networking architecture. The figure includes the devices in the EVPN-VXLAN IP Fabric as well as the SDN gateway routers, whose configuration is beyond the scope of this reference architecture.

Figure 1: Reference Architecture High-level OverviewReference Architecture High-level Overview

The following information is provided in this document:

  • Server hardware recommendations for each type of node to achieve optimal scale and performance.

  • NIC configuration and network connectivity for each node type.

  • Recommended BIOS settings.

  • Network addressing scheme for servers.

  • Detailed specification of capabilities needed in the networking infrastructure.

  • Recommendations for Juniper device models for each network role.

  • Configuration examples from each network device type showing how the various networking requirements can be met by configuring an IP Fabric using Juniper devices.


This reference architecture provides some information related to connecting nodes to the end fabric, but does not provide in-depth coverage of fabric provisioning and configuration. See Data Center Fabric Architecture Guide.