Understanding Ex9214 Switch Component And Functionality Redundancy; Line Cards - Juniper EX9214 Hardware Manual

Understanding EX9214 Switch Component and Functionality Redundancy

Copyright © 2017, Juniper Networks, Inc.
Installing and Removing EX9208 Switch Hardware Components
Installing and Removing EX9214 Switch Hardware Components on page 144
The Juniper Networks EX9214 Ethernet Switch is available as a fully redundant system.
A redundant EX9214 switch configuration is so designed that no single point of failure
can cause the entire switch to fail. See
The following hardware components provide redundancy to an EX9214 switch:
Host subsystem—The host subsystem consists of a Routing Engine functioning together
with a Switch Fabric. The host subsystem performs switching and routing functionality,
system management, and system control functions of the switch. Either two or three
host subsystems can be installed in the switch. If two host subsystems are installed,
one functions as the master and the other functions as the backup. If the master host
subsystem (or either of its components) fails, the backup takes over as the master.
To operate, each host subsystem requires a Routing Engine module (RE module)
installed directly into in a Switch Fabric module (SF module).
You can install up to 12 line cards in an EX9214 switch. You can install either a line card
or an SF module in the slot nine (labeled
(labeled ), redundancy is not available for the host subsystem.
2 | 6
If the Routing Engines are configured for graceful switchover, the backup Routing Engine
automatically synchronizes its configuration and state with the master Routing Engine.
Any update to the master Routing Engine state is replicated on the backup Routing
Engine. If the backup Routing Engine assumes mastership, packet forwarding continues
through the switch without interruption.
AC power supplies—You can install either two or four AC power supplies vertically at
the rear of the chassis in slots
operate in two zones: power supplies in slots
lower fan tray, line-card slots
in slots and
PEM1 PEM3
, and switch fabric slot
5
power supplies provide full redundancy. If a power supply in a redundant configuration
is removed or fails, its redundant power supply takes over without interruption. The
power supply in serves as redundant power supply to the power supply in slot
PEM2
and the power supply in
PEM0
supply in slot PEM1 . If only two power supplies are installed, they must be installed in
slots and or in slots
PEM0 PEM1
Switch" on page 45.
DC power supplies—You can install four DC power supplies vertically at the rear of the
chassis in slots PEM0 through
zones: power supplies in slots
line-card slots through
6
and PEM3 provide power to the upper fan tray, line-card slots
fabric slot . There must be at least one power supply in each zone. Four power supplies
0
Chapter 2: Chassis Components and Descriptions
"EX9214 Switch Configurations" on page
2 | 6 ). If you install a line card in slot nine
through
PEM0 PEM3
PEM0
6 through 11 , and switch fabric slots
provide power to the upper fan tray, line-card slots
. There must be at least one power supply in each zone. Four
0
serves as redundant power supply to the power
PEM3
and . See
PEM2 PEM3
PEM3 (left to right). The power supplies operate in two
and provide power to the lower fan tray,
PEM0 PEM2
, and switch fabric slots
11 1
(left to right). The power supplies
and provide power to the
PEM2
1 and 2 ; power supplies
0
"AC Power Supply in an EX9214
and ; power supplies in slots
2
0 through 5 , and switch
8.
through
PEM1
21