Juniper QFX3000-G QFabric, Deployment Manual, Page: 33 / 652

Understanding QFabric System Terminology
Supported Platforms
QFabric System
To understand the QFabric system environment and its components, you should become
familiar with the terms defined in
Table 3 on page 7 .
Table 3: QFabric System Terms
Definition Term
Three-stage switching network in which switch elements in the middle stages
are connected to all switch elements in the ingress and egress stages. In the
case of QFabric system components, the three stages are represented by an
ingress chipset, a midplane chipset, and an egress chipset in an Interconnect
device (such as a QFX3008-I Interconnect device). In Clos networks, which
are well known for their nonblocking properties, a connection can be made
from any idle input port to any idle output port, regardless of the traffic load
in the rest of the system. Clos network fabric
Hardware component that processes fundamental QFabric system applications
and services, such as startup, maintenance, and inter-QFabric system device
communication. A set of Director devices with hard drives can be joined to form
a
Director group , which provides redundancy and high availability by way of
additional memory and processing power. (See also Director group .)
Director device
Set of Director devices that host and load-balance internal processes for the
QFabric system. The Director group handles tasks such as QFabric system
network topology discovery, Node and Interconnect device configuration,
startup, and DNS, DHCP, and NFS services. Operating a Director group is a
minimum requirement to manage a QFabric system.
The Director group runs the Director software for management applications
and runs dual processes in active/standby mode for maximum redundancy
and high availability. (See also
Director software and Director device .)
Director group
Software that handles QFabric system administration tasks, such as fabric
management and configuration. The Junos OS-based Director software runs
on the
Director group , provides a single, consolidated view of the QFabric
system, and enables the main QFabric system administrator to configure,
manage, monitor, and troubleshoot QFabric system components from a
centralized location. To access the Director software, log in to the default
partition. (See also
Director device and Director group .)
Director software
Virtual Junos OS Routing Engine instance used to control the exchange of
routes and flow of data between QFabric system hardware components within
a partition. The fabric control Routing Engine runs on the Director group. fabric control Routing Engine
Virtual Junos OS Routing Engine instance used to control the initialization and
maintenance of QFabric system hardware components belonging to the default
partition. The fabric manager Routing Engine runs on the Director group. fabric manager Routing Engine
QFabric system services processed by the virtual Junos Routing Engines
operating within the Director group. These services, such as fabric management
and fabric control, support QFabric system functionality and high availability. infrastructure
7 Copyright © 2015, Juniper Networks, Inc.
Chapter 1: Before You Begin