Extreme Networks Extreme 7520 Series Manual

Extreme 7520 Hardware Installation Guide
9037389-00 Rev. AA
July 2023

Copyright © 2023 Extreme Networks, Inc. All rights reserved.
Legal Notice
Extreme Networks, Inc. reserves the right to make changes in specications and other
information contained in this document and its website without prior notice. The reader should
in all cases consult representatives of Extreme Networks to determine whether any such changes
have been made.
The hardware, rmware, software or any specications described or referred to in this document
are subject to change without notice.
Trademarks
Extreme Networks and the Extreme Networks logo are trademarks or registered trademarks of
Extreme Networks, Inc. in the United States and/or other countries.
All other names (including any product names) mentioned in this document are the property
of their respective owners and may be trademarks or registered trademarks of their respective
companies/owners.
For additional information on Extreme Networks trademarks, see: www.extremenetworks.com/
company/legal/trademarks
Open Source Declarations
Some software les have been licensed under certain open source or third-party licenses.
End-user license agreements and open source declarations can be found at: https://
www.extremenetworks.com/support/policies/open-source-declaration/

Table of Contents
Preface.............................................................................................................................................. 7
Audience.................................................................................................................................................................................................... 7
Text Conventions..................................................................................................................................................................................7
Documentation and Training....................................................................................................................................................9
Help and Support................................................................................................................................................................................9
Subscribe to Product Announcements.................................................................................................................10
Send Feedback................................................................................................................................................................................... 10
Extreme 7520 Series Overview................................................................................................12
Management........................................................................................................................................................................................ 12
Cooling....................................................................................................................................................................................................... 12
Power Supplies.................................................................................................................................................................................... 13
Stacking.....................................................................................................................................................................................................13
Operating Temperatures.............................................................................................................................................................14
Feature Licensing..............................................................................................................................................................................14
Extreme 7520-48Y-8C Switch Features........................................................................................................................... 14
Extreme 7520-48XT-6C Switch Features.........................................................................................................................15
Port Partitions...............................................................................................................................17
Power Supplies for Use with Your Switch...........................................................................18
Precautions Specic to Power Supply Modules........................................................................................................18
800 W AC Power Supply..............................................................................................................................................................19
800 W DC Power Supply............................................................................................................................................................. 19
Build Stacks.................................................................................................................................. 20
Introduction to Stacking............................................................................................................................................................ 20
Build Basic Stacks....................................................................................................................................................................21
SummitStack Topologies................................................................................................................................................. 22
SummitStack Terms.............................................................................................................................................................25
Plan to Create Your Stack...........................................................................................................................................................29
Enable and Disable the Stacking-Support Option......................................................................................29
Recommendations for Placing Switches for Stacked Operation.....................................................29
Recommendations for Conguring Stacks.......................................................................................................30
Combine Switches from Different Series..............................................................................................................31
Select Stacking Cables........................................................................................................................................................ 31
Use the Extreme Stacking Tool.....................................................................................................................................31
Set up the Physical Stack...........................................................................................................................................................33
Connect the Switches to Form the Stack Ring...............................................................................................33
Connect Your Stack to the Management Network.....................................................................................36
Site Preparation........................................................................................................................... 37
Plan Your Site.......................................................................................................................................................................................37
Operating Environment Requirements.........................................................................................................................38
Extreme 7520 Hardware Installation Guide iii

Meet Building and Electrical Codes........................................................................................................................38
Set Up the Wiring Closet.................................................................................................................................................. 39
Control the Temperature.................................................................................................................................................40
Control the Humidity Level..............................................................................................................................................41
Protect Your System from ESD (Electrostatic Discharge).......................................................................41
Rack Specications and Recommendations.............................................................................................................. 41
Mechanical Recommendations for the Rack.................................................................................................. 42
Ground the Rack.....................................................................................................................................................................42
Provide Adequate Space for the Rack...................................................................................................................42
Secure the Rack.......................................................................................................................................................................43
Evaluate and Meet Cable Requirements...................................................................................................................... 43
Label Cables and Keep Accurate Records..........................................................................................................44
Install Cable................................................................................................................................................................................44
Use RJ45 Connector Jackets.........................................................................................................................................48
Prevent Radio Frequency Interference (RFI)....................................................................................................48
Meet Power Requirements......................................................................................................................................................49
Requirements for PoE Devices................................................................................................................................... 49
Power Supply Requirements........................................................................................................................................49
Power Cord Requirements............................................................................................................................................. 50
UPS (Uninterruptible Power Supply) Requirements.................................................................................50
Follow Applicable Industry Standards..............................................................................................................................51
Install the Switch.........................................................................................................................52
Safety Considerations for Installation............................................................................................................................... 52
What You Will Need for the Installation......................................................................................................................... 53
Attach the Switch to a Rack or Cabinet.......................................................................................................................... 53
Four-Post Rack Mount.......................................................................................................................................................54
Two-Post Rack Mount.........................................................................................................................................................57
Install Optional Components..................................................................................................................................................59
Pluggable Transceiver Modules..................................................................................................................................59
Optical Cables...........................................................................................................................................................................60
Breakout cables.......................................................................................................................................................................60
Install Internal Power Supplies..............................................................................................................................................60
Install an 800 W Internal AC Power Supply......................................................................................................60
Install an 800 W Internal DC Power Supply......................................................................................................63
Turn on the Switch..........................................................................................................................................................................66
Connect Network Interface Cables.................................................................................................................................... 67
Activate and Verify the Switch.............................................................................................. 68
Connect to a Management Console.................................................................................................................................68
Log in for the First Time on SwitchEngine................................................................................................................. 68
Congure the Switch's IP Address for the Management VLAN..................................................................70
Change the Switch OS via the Bootloader Menu...................................................................................................70
Change the Switch OS via the Startup Menu.............................................................................................................71
Log In for the First Time on FabricEngine....................................................................................................................71
Remove and Replace Components...................................................................................... 73
Replace Internal Power Supplies......................................................................................................................................... 73
Replace Fan Modules.................................................................................................................................................................... 73
Remove the Device from the Rack.....................................................................................................................................74
Remove the Switch from a Four-Post Rack.......................................................................................................74
Table of Contents
iv Extreme 7520 Hardware Installation Guide

Remove the Switch from a Two-Post Rack........................................................................................................76
Monitor the Switch.....................................................................................................................78
System Status LEDs........................................................................................................................................................................78
RJ-45 Management Port LEDs..............................................................................................................................................79
SFP+/SFP28 Port LEDs for the 7520-48Y-8C..............................................................................................................80
1G/10G RJ45 Port LEDs for the 7520-48XT-6C.............................................................................................................81
QSFP28 Port LEDs............................................................................................................................................................................81
800 W AC Power Supply LEDs...............................................................................................................................................82
800 W DC Power Supply LEDs..............................................................................................................................................82
Technical Specications.......................................................................................................... 84
Software Specications............................................................................................................................................................... 84
Weights and Physical Dimensions.....................................................................................................................................85
Acoustic Specications................................................................................................................................................................87
Fan Tray and Speed Variation.................................................................................................................................................88
Power Consumption..................................................................................................................................................................... 88
7520-48Y........................................................................................................................................................................................89
7520-48XT...................................................................................................................................................................................... 91
Power and Heat Dissipation.................................................................................................................................................... 93
Mean Time Between Failures................................................................................................................................................. 93
CPU, Memory Specications................................................................................................................................................... 93
Standards............................................................................................................................................................................................... 94
Environmental Standards............................................................................................................................................... 96
800 W Power Supplies Technical Specications.....................................................................................................96
Power Cord Requirements for AC-Powered Switches and AC Power Supplies.............................98
Console Connector Pinouts..................................................................................................................................................... 99
Safety Information.................................................................................................................... 102
Considerations Before Installing........................................................................................................................................ 102
General Safety Precautions.....................................................................................................................................................103
Maintenance Safety..................................................................................................................................................................... 104
Fiber Optic Ports and Optical Safety..............................................................................................................................104
Cable Routing for LAN Systems..........................................................................................................................................105
Install Power Supply Units and Connect Power.................................................................................................... 105
Select Power Supply Cords.....................................................................................................................................................106
Battery Notice................................................................................................................................................................................... 107
Battery Warning - Taiwan........................................................................................................................................................107
Regulatory Information.......................................................................................................... 108
CE statement.....................................................................................................................................................................................108
EMC Warnings..................................................................................................................................................................................109
China CQC Warning...........................................................................................................................................................109
China and Taiwan: Restriction of Hazardous Substances (ROHS)...........................................................109
BSMI statement (Taiwan).........................................................................................................................................................109
Canadian requirements............................................................................................................................................................109
China CCC statement.................................................................................................................................................................. 110
Australia (RCM).................................................................................................................................................................................. 110
Federal Communications Commission (FCC) Notice.........................................................................................110
Germany statement....................................................................................................................................................................... 111
KCC statement (Republic of Korea)....................................................................................................................................111
Japan (VCCI Class A)....................................................................................................................................................................... 111
Table of Contents
Extreme 7520 Hardware Installation Guide v

Japan power cord ...........................................................................................................................................................................112
Index............................................................................................................................................... 113
Table of Contents
vi Extreme 7520 Hardware Installation Guide

Preface
Read the following topics to learn about:
•The meanings of text formats used in this document.
•Where you can nd additional information and help.
•How to reach us with questions and comments.
Audience
This guide is intended for use by network administrators responsible for installing and
setting up network equipment. It assumes a basic working knowledge of:
•Local area networks (LANs)
•Ethernet concepts
•Ethernet switching and bridging concepts
•Routing concepts
•Simple Network Management Protocol (SNMP)
•Basic equipment installation procedures
See the SwitchEngine 32.4 User Guide and the SwitchEngine 32.4 Command
Reference Guide for information about conguring Extreme Networks devices.
Note
If the information in an installation note or release note shipped with your
Extreme Networks equipment differs from the information in this guide, follow
the installation or release note.
Text Conventions
Unless otherwise noted, information in this document applies to all supported
environments for the products in question. Exceptions, like command keywords
associated with a specic software version, are identied in the text.
When a feature, function, or operation pertains to a specic hardware product, the
product name is used. When features, functions, and operations are the same across an
entire product family, such as ExtremeSwitching switches or SLX routers, the product is
referred to as the switch or the router .
Extreme 7520 Hardware Installation Guide 7

Table 1: Notes and warnings
Icon Notice type Alerts you to...
Tip Helpful tips and notices for using the product
Note Useful information or instructions
Important Important features or instructions
Caution Risk of personal injury, system damage, or loss of
data
Warning Risk of severe personal injury
Table 2: Text
Convention Description
screen displays This typeface indicates command syntax, or represents
information as it is displayed on the screen.
The words enter and
type
When you see the word enter in this guide, you must type
something, and then press the Return or Enter key. Do not
press the Return or Enter key when an instruction simply
says type .
Key names Key names are written in boldface, for example Ctrl or Esc.
If you must press two or more keys simultaneously, the
key names are linked with a plus sign (+). Example: Press
Ctrl+Alt+Del
Words in italicized type Italics emphasize a point or denote new terms at the place
where they are dened in the text. Italics are also used
when referring to publication titles.
New information. In a PDF, this is searchable text.
Table 3: Command syntax
Convention Description
bold text Bold text indicates command names, keywords, and
command options.
italic text Italic text indicates variable content.
Text Conventions Preface
8Extreme 7520 Hardware Installation Guide

Table 3: Command syntax (continued)
Convention Description
[ ] Syntax components displayed within square brackets are
optional.
Default responses to system prompts are enclosed in
square brackets.
{ x | y | z } A choice of required parameters is enclosed in curly
brackets separated by vertical bars. You must select one of
the options.
x | yA vertical bar separates mutually exclusive elements.
< > Nonprinting characters, such as passwords, are enclosed in
angle brackets.
... Repeat the previous element, for example,
member[member...].
\ In command examples, the backslash indicates a “soft” line
break. When a backslash separates two lines of a command
input, enter the entire command at the prompt without the
backslash.
Documentation and Training
Find Extreme Networks product information at the following locations:
Current Product Documentation
Release Notes
Hardware and software compatibility for Extreme Networks products
Extreme Optics Compatibility
Other resources such as white papers, data sheets, and case studies
Extreme Networks offers product training courses, both online and in person, as well as
specialized certications. For details, visit www.extremenetworks.com/education/.
Help and Support
If you require assistance, contact Extreme Networks using one of the following
methods:
Extreme Portal
Search the GTAC (Global Technical Assistance Center) knowledge base; manage
support cases and service contracts; download software; and obtain product
licensing, training, and certications.
The Hub
A forum for Extreme Networks customers to connect with one another, answer
questions, and share ideas and feedback. This community is monitored by Extreme
Networks employees, but is not intended to replace specic guidance from GTAC.
Call GTAC
Preface Documentation and Training
Extreme 7520 Hardware Installation Guide 9

For immediate support: [phone] (toll-free in U.S. and Canada) or
1 [phone]. For the support phone number in your country, visit:
www.extremenetworks.com/support/contact
Before contacting Extreme Networks for technical support, have the following
information ready:
•Your Extreme Networks service contract number, or serial numbers for all involved
Extreme Networks products
•A description of the failure
•A description of any actions already taken to resolve the problem
•A description of your network environment (such as layout, cable type, other
relevant environmental information)
•Network load at the time of trouble (if known)
•The device history (for example, if you have returned the device before, or if this is a
recurring problem)
•Any related RMA (Return Material Authorization) numbers
Subscribe to Product Announcements
You can subscribe to email notications for product and software release
announcements, Field Notices, and Vulnerability Notices.
1. Go to The Hub.
2. In the list of categories, expand the Product Announcements list.
3. Select a product for which you would like to receive notications.
4. Select Subscribe.
5. To select additional products, return to the Product Announcements list and repeat
steps 3 and 4.
You can modify your product selections or unsubscribe at any time.
Send Feedback
The Information Development team at Extreme Networks has made every effort to
ensure that this document is accurate, complete, and easy to use. We strive to improve
our documentation to help you in your work, so we want to hear from you. We welcome
all feedback, but we especially want to know about:
•Content errors, or confusing or conicting information.
•Improvements that would help you nd relevant information.
•Broken links or usability issues.
To send feedback, do either of the following:
•Access the feedback form at https://www.extremenetworks.com/documentation-
feedback/.
•Email us at [e-mail].
Subscribe to Product Announcements Preface
10 Extreme 7520 Hardware Installation Guide

Provide the publication title, part number, and as much detail as possible, including
the topic heading and page number if applicable, as well as your suggestions for
improvement.
Preface Send Feedback
Extreme 7520 Hardware Installation Guide 11

Extreme 7520 Series Overview
Extreme 7520-48Y-8C Switch Features on page 14
Extreme 7520-48XT-6C Switch Features on page 15
The Extreme 7520 Series are purpose-built 48-port 10Gb and 48-port 25Gb switches
designed for high-performance aggregation and core applications. The Extreme 7520
provides end-to-end secure network segmentation and advanced policy capabilities.
The 7520 Series are Universal Hardware, providing a user-selectable choice of Extreme’s
agship switch operating systems.
The 7520 Series network hardware platform enables organizations to design networks
that accommodate a variety of applications and east-west trafc patterns. With its
high-density scale-out architecture, leading power efciency, and airow options, the
7520 Series platform delivers a cost-effective solution that optimizes power, cooling,
and equipment room space, wherever your network operating center might be.
Management
An RJ45 serial console port on the front panel of the 7520 Series switch enables you to
connect a terminal and perform local management. An RJ-45 Ethernet management
port can also be used to connect the system to an out of band management network
for administration. Alternatively, you can use an Ethernet cable to connect this port
directly to a laptop to view and locally manage the switch conguration. The Ethernet
management port supports 10/100/1000 Mbps speeds.
There is also a Type A USB 2.0 port that can host removable devices like ash drives.
Cooling
Hot-swappable fan modules that provide either front-to-back or back-to-front airow
for switch cooling are available for 7520 Series switches. The six fan slots on all models
are located on the rear panel. Switch fans are not responsible for cooling the power
supplies; power supplies have integrated cooling fans that operate independently of
the switch fan. The direction of the airow in the fans and power supplies must be the
same.
12 Extreme 7520 Hardware Installation Guide

Fans are ordered separately for base models 7520-48Y-8C and 7520-48XT-6C. Fans are
included with other models.
Power Supplies
Hot swappable 800 W AC or DC power supplies are available to power the switch. The
power supplies have integrated cooling fans that operate independently of the switch
fans. The fans provide either front-to-back or back-to-front airow. The direction of the
airow in the power supplies and the switch fans must be the same. The two power
supply slots on all models are located on the rear panel. For more information about
the power supplies used in the 7520 Series switches, see Power Supplies for Use with
Your Switch on page 18.
Power supplies are ordered separately for base models 7520-48Y-8C and 7520-48XT-6C.
Power supplies are included with other models.
Stacking
Each 7520 Series switch comes equipped with two high-speed 100Gb stacking ports,
also referred to as Universal Ethernet ports. When running Switch Engine, up to
eight systems can be stacked using qualied QSFP28 direct attach cables and optical
transceivers located on the front panel of the switch. Stacking is not supported when
running Fabric Engine. The stacking ports on 7520-48XT-6C models are ports 53 and 54.
The stacking ports on 7520-48Y-8C models are ports 55 and 56.
Note
The two stacking/QSFP ports are “Universal Ethernet” ports. These ports can
operate either as stacking ports with Switch Engine or as Ethernet ports with
Switch Engine and with Fabric Engine in non-fabric mode.
By default the stacking ports operate as Ethernet ports. Use the enable stacking-
support command to set the stacking ports in stacking mode.
When running Fabric Engine, the stacking (or Universal Ethernet) ports are reserved
for use by advanced features on the switch by default. For more information, see
the advanced-feature-bandwidth-reservation Boot Flag documentation in the Fabric
Engine User Guide for your version of the FabricEngine operating system located at
https://www.extremenetworks.com/support/documentation/fabric-engine/
Stacking cables for 7520 Series switches are ordered separately.
For information about QSFP28 and QSFP+ optical modules, see the Extreme Optics
website.
Extreme 7520 Series Overview Power Supplies
Extreme 7520 Hardware Installation Guide 13

Operating Temperatures
The 7520 Series supports the following operating temperatures with front-to-back
cooling:
•0°C (32°F) to 50°C (122°F) at sea level
•0°C (32°F) to 40°C (104°F) up to 3000 m (10,000 ft)
The 7520 Series supports the following operating temperatures with back-to-front
cooling:
•0°C (32°F) to 45°C (113°F) at sea level
•0°C (32°F) to 40°C (104°F) up to 3000 m (10,000 ft)
Feature Licensing
The 7520 Series switches support Unied Licensing, so that you can use them with
multiple operating systems. There are two methods of acquiring feature licenses:
manual or through ExtremeCloud™ IQ (XIQ).
For SwitchEngine licensing, see SwitchEngine 32.4 Feature License Requirements .
For FabricEngine licensing, see the Fabric Engine User Guide for your version of the
FabricEngine operating system located at https://www.extremenetworks.com/support/
documentation/fabric-engine/.
For XIQ licensing, see Licensing Information .
Extreme 7520-48Y-8C Switch Features
The Extreme 7520-48Y-8C switch includes the following models:
7520-48Y-8C
The 7520-48Y-8C base switch includes six empty fan module slots and two empty
power supply module slots. Fan modules and power supply modules must be
ordered separately.
7520-48Y-8C-AC-F
The 7520-48Y-8C-AC-F switch includes two AC power supply modules and six fan
modules. Airow for both the fan modules and the powers supply modules is front-
to-back.
7520-48Y-8C-AC-R
The 7520-48Y-8C-AC-R switch includes two AC power supply modules and six fan
modules. Airow for both the fan modules and the powers supply modules is back-
to-front.
The front panel of the switch includes:
•48 1/10/25Gbps SFP28 ports
•8 40/100Gbps QSFP28 ports
•1 RJ-45 serial console RJ-45 port
Operating Temperatures Extreme 7520 Series Overview
14 Extreme 7520 Hardware Installation Guide

•1 10/100/1000BASE-T out-of-band management port
•1 Type A USB storage port
Figure 1: 7520-48Y-8C Switch Front Panel
1 = 1/10/25Gbps SFP28
ports
3 = 10/100/1000BASE-T OOB
management port
5 = RJ-45 serial
console port
2 = 40/100Gbps QSFP28
port
4 = USB Type A port 6 = System LEDs
The rear panel of the switch includes:
•6 fan module slots
•Grounding lug
•2 power supply slots
Figure 2: 7520-48Y-8C Switch Rear Panel
1 = Grounding lug 2 = Power supply slots 3 = Fan module slots
Extreme 7520-48XT-6C Switch Features
The Extreme 7520-48XT-6C switch includes the following models:
7520-48XT-6C
The 7520-48XT-6C base switch includes six empty fan module slots and two empty
power supply module slots. Fan modules and power supply modules must be
ordered separately
7520-48XT-6C-AC-F
The 7520-48XT-6C-AC-F switch includes two AC power supply modules and six fan
modules. Airow for both the fan modules and the powers supply modules is front-
to-back.
7520-48XT-6C-AC-R
The 7520-48XT-6C-AC-R switch includes two AC power supply modules and six fan
modules. Airow for both the fan modules and the powers supply modules is back-
to-front.
Extreme 7520 Series Overview Extreme 7520-48XT-6C Switch Features
Extreme 7520 Hardware Installation Guide 15

The front panel of the switch includes:
•48 1/10Gbps 10GBaseT RJ-45 ports
•6 40/100Gbps QSFP28 ports
•1 RJ-45 serial console port
•1 10/100/1000BASE-T out-of-band management port
•1 Type A USB storage port
Figure 3: 7520-48XT-6CSwitch Front Panel
1 = 1/10GbE 10GBaseT
RJ-45 ports
3 = 10/100/1000BASE-T OOB
management port
5 = Serial console
port RJ-45
2 = 40/100Gbe QSFP28
ports
4 = USB Type A port 6 = System LEDs
The rear panel of the switch includes:
•6 fan module slots
•Grounding lug
•2 power supply slots
Figure 4: 7520-48XT-6C Switch Rear Panel
1 = Grounding lug 2 = Power supply slots 3 = Fan module slots
Extreme 7520-48XT-6C Switch Features Extreme 7520 Series Overview
16 Extreme 7520 Hardware Installation Guide

Port Partitions
On some ExtremeSwitching switch models, you can congure QSFP28 and QSFP+
ports either as single ports or as multiple, partitioned ports. In a partitioned port, with
appropriate cabling, the original physical port can accommodate multiple data lanes at
lower bandwidths.
The following partitioning options are available:
Table 4: QSFP28 Port Partitioning
Switch model Port
bandwidth
Port partitions
Fabric Engine Switch Engine
7520 (all
models)
QSFP28
100 Gb or 40
Gb
One QSFP28 ports with
one of the following:
• One 100 Gb port
• One 40 Gb port
• Four 25 Gb ports
• Four 10 Gb ports
Two QSFP28 ports with
one of the following:
• One 100 Gb port
• One 40 Gb port
• Four 25 Gb ports
• Four 10 Gb ports
Extreme 7520 Hardware Installation Guide 17

Power Supplies for Use with Your
Switch
Each 7520 Series switch runs with two replaceable internal power supply modules that
provide all of the power needed for the switch to operate. You can remove one power
supply module without interrupting the switch's operation. Supported power supply
congurations include two 800 W AC power supply modules, two 800 W DC power
supply modules, or one 800 W AC and one 800 W DC power supply module. Power
supply modules have integrated cooling fans that operate independently of the switch
fans, and are available with front-to-back or back-to-front airow. The direction of the
airow in both power supply modules must be in the same direction, and must also be
the in same direction of the airow in the fan modules.
Power supply modules are ordered separately for base models 7520-48Y-8C and
7520-48XT-6C. Power supply modules are included with other models.
Precautions Specic to Power Supply Modules
Warning
Make sure that the power source circuits are properly grounded, then use the
power cord supplied with the device to connect it to the power source.
Warning
If the installation requires a different power cord than the one supplied with
the device, make sure you use a power cord displaying the mark of the safety
agency that denes the regulations for power cords in your country. The mark
is your assurance that the power cord can be used safely with the device.
Caution
Disassembling any part of the power supply and fan assembly voids the
warranty and regulatory certications. There are no user-serviceable parts
inside the power supply and fan assembly.
Caution
Ensure that the airow direction of the power supply unit matches that of
the installed fan tray. The power supplies and fan trays are clearly labeled with
either a green arrow with an "E", or an orange arrow with an "I."
18 Extreme 7520 Hardware Installation Guide

Caution
If you do not install a module or a power supply in a slot, you must keep the
slot ller panel in place. If you run the chassis with an uncovered slot, the
system will overheat.
800 W AC Power Supply
Two 800 W AC power supply options, with front-to-back or back-to-front airow, are
supported on Extreme 7520 switches.
•800W AC power supply - front-to-back airow (part no. XN-ACPWR-800W-F)
•800W AC power supply - back-to-front airow (part no. XN-ACPWR-800W-R)
Note
AC power input cords are not provided with AC power supplies. You can order
an appropriate cord from Extreme Networks or from your local supplier. The
power cord must meet the requirements listed in Power Cord Requirements
for AC-Powered Switches and AC Power Supplies on page 98.
For information on installing or replacing an AC power supply, see Install an 800 W
Internal AC Power Supply on page 60.
LEDs on the 800 W AC power supply provide information on the unit's operational
status. See 800 W AC Power Supply LEDs on page 82 for details.
800 W DC Power Supply
Two 800 W DC power supply options, with front-to-back or back-to-front airow, are
provided for 7520 switches.
•800W DC power supply - front-to-back airow (part no. XN-DCPWR-800W-F)
•800W DC power supply - back-to-front airow (part no. XN-DCPWR-800W-R)
Note
DC power input cords are not provided with DC power supplies. You can order
an appropriate cord from Extreme Networks or from your local supplier.
For information on installing or replacing a DC power supply, see Install an 800 W
Internal DC Power Supply on page 63.
LEDs on the 800 W DC power supply provide information on the unit's operational
status. See 800 W DC Power Supply LEDs on page 82 for details.
Power Supplies for Use with Your Switch 800 W AC Power Supply
Extreme 7520 Hardware Installation Guide 19

Build Stacks
Introduction to Stacking on page 20
Plan to Create Your Stack on page 29
Set up the Physical Stack on page 33
A stack consists of a group of up to eight switches that are connected to form a ring.
The stack offers the combined port capacity of the individual switches; it operates as if
it were a single switch, making network administration easier.
Stacking is facilitated by the SummitStack feature – part of the SwitchEngine and
ExtremeXOS Edge license.
This topic describes the supported congurations for stacking switches, the
considerations for planning a stack, and the steps for setting up the hardware. Read
this chapter before installing the switches that will make up the stack.
Refer to the Stacking chapter in the SwitchEngine 32.4 User Guide for information
about conguring a stack, maintaining the stack conguration, and troubleshooting.
Introduction to Stacking
When stacking switches, the stack operates as if it were a single switch with a single IP
address and a single point of authentication. One switch – called the primary switch –
is responsible for running network protocols and managing the stack. The primary runs
SwitchEngine software and maintains all the software tables for all the switches in the
stack.
All switches in the stack, including the primary switch, are called nodes. Figure 5 shows
four nodes in a stack, connected to each other by SummitStack cables.
All connections between stack ports must be directly between switches. A stacking
connection cannot pass through a third device, for example a Virtual Port Extender or
an LRM/MACsec Adapter.
20 Extreme 7520 Hardware Installation Guide