959 juniper MX series

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Juniper MX Series

Douglas Richard Hanks, Jr. and Harry Reynolds

Beijing • Cambridge • Farnham • Köln • Sebastopol • Tokyo

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Juniper MX Series
by Douglas Richard Hanks, Jr. and Harry Reynolds
Copyright © 2012 Douglas Hanks, Jr., Harry Reynolds. All rights reserved.
Printed in the United States of America.
Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472.
O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions
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corporate/institutional sales department: 800-998-9938 or

Editors: Mike Loukides and Meghan Blanchette
Development Editor: Patrick Ames
Production Editor: Holly Bauer
Copyeditor: Absolute Service, Inc.
Proofreader: Rachel Leach
October 2012:

Indexer: Bob Pfahler
Cover Designer: Karen Montgomery
Interior Designer: David Futato
Illustrator: Rebecca Demarest

First Edition.

Revision History for the First Edition:
2012-09-24
First release
See for release details.

Nutshell Handbook, the Nutshell Handbook logo, and the O’Reilly logo are registered trademarks of
O’Reilly Media, Inc. Juniper MX Series, the image of a tawny-shouldered podargus, and related trade
dress are trademarks of O’Reilly Media, Inc.
Many of the designations used by manufacturers and sellers to distinguish their products are claimed as
trademarks. Where those designations appear in this book, and O’Reilly Media, Inc., was aware of a
trademark claim, the designations have been printed in caps or initial caps.
While every precaution has been taken in the preparation of this book, the publisher and authors assume
no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein.

ISBN: 978-1-449-31971-7
[LSI]
1348575579

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Dedicated to my wife and my parents. You guys
are the best. Love you.

—Douglas

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I would like to acknowledge my wife, Anita, and
our two lovely daughters, Christina and Marissa,
for once again understanding and accommodating
my desire to engage in this project. And thanks to
Doug, that plucky young lad who managed to
goad me into engaging in this project when my day
job was already rather action-packed. A special
thanks to my manager, Andrew Pangelinan at
Juniper Networks, for his understanding and
support in this project.
—Harry

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Table of Contents

About the Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii

1. Juniper MX Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Junos
One Junos
Software Releases
Three Release Cadence
Software Architecture
Daemons
Routing Sockets
Juniper MX Chassis
MX80
Midrange
MX240
MX480
MX960
Trio
Trio Architecture
Buffering Block
Lookup Block
Interfaces Block
Dense Queuing Block
Line Cards and Modules
Dense Port Concentrator
Modular Port Concentrator
Packet Walkthrough
Modular Interface Card
Network Services
Switch and Control Board

2
3

3
4
5
6
11
13
14
17
18
20
21
24
25
26
27
28
30
30
31
32
41
44
46
47

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Ethernet Switch
Switch Fabric
J-Cell
MX Switch Control Board
Enhanced MX Switch Control Board
MX2020
Architecture
Summary
Chapter Review Questions
Chapter Review Answers

48
52
55
57
60
61
61
67
69
70

2. Bridging, VLAN Mapping, IRB, and Virtual Switches . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Isn’t the MX a Router?
Layer 2 Networking
Ethernet II
IEEE 802.1Q
IEEE 802.1QinQ
Junos Interfaces
Interface Bridge Configuration

Basic Comparison of Service Provider versus Enterprise Style
Service Provider Interface Bridge Configuration
Tagging
Encapsulation
Service Provider Bridge Domain Configuration
Enterprise Interface Bridge Configuration
Interface Mode
VLAN Rewrite
Service Provider VLAN Mapping
Stack Data Structure
Stack Operations
Stack Operations Map
Tag Count
Bridge Domain Requirements
Example: Push and Pop
Example: Swap-Push and Pop-Swap
Bridge Domains
Learning Domain
Bridge Domain Modes
Bridge Domain Options
Show Bridge Domain Commands
Clear MAC Addresses
MAC Accounting
Integrated Routing and Bridging

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71

73
73
74
75
77
80
80
83
84
87
91
94
94
97
99
99
100
103
106
107
107
109
111
112
115
131
135
137
139
141

IRB Attributes
Virtual Switch
Configuration
Summary
Chapter Review Questions
Chapter Review Answers

142
144
145
149
150
151

3. Stateless Filters, Hierarchical Policing, and Tri-Color Marking . . . . . . . . . . . . . . . . 153
Firewall Filter and Policer Overview
Stateless versus Stateful
Stateless Filter Components
Filters versus Routing Policy
Filter Scaling
Filtering Differences for MPC versus DPC
Enhanced Filter Mode
Filter Operation
Stateless Filter Processing
Policing
Rate Limiting: Shaping or Policing?
Junos Policer Operation
Basic Policer Example

Cascaded Policers
Single and Two-Rate Three-Color Policers
Hierarchical Policers
Applying Filters and Policers
Filter Application Points
Applying Policers
Policer Application Restrictions
Bridge Filtering Case Study
Filter Processing in Bridged and Routed Environments
Monitor and Troubleshoot Filters and Policers
Bridge Family Filter and Policing Case Study
Summary
Chapter Review Questions
Chapter Review Answers

153
154
155
161
163
166
166
167
167
173
173
178
180
181
184

192
195
195
200
212
213
213
214
221
230
231
233

4. Routing Engine Protection and DDoS Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
RE Protection Case Study
IPv4 RE Protection Filter
IPv6 RE Protection Filter
DDoS Protection Case Study
The Issue of Control Plane Depletion
DDoS Operational Overview

235
236
260
271
272
273
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Configuration and Operational Verification
Late Breaking DDoS Updates
DDoS Case Study
The Attack Has Begun!
Mitigate DDoS Attacks
BGP Flow-Specification to the Rescue
Summary
BGP Flow-Specification Case Study
Let the Attack Begin!
Summary
Chapter Review Questions
Chapter Review Answers

279
287
287
289
294
295
301
301
306
314
315
316

5. Trio Class of Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
MX CoS Capabilities

Port versus Hierarchical Queuing MPCs
CoS Capabilities and Scale
Trio CoS Flow
Intelligent Oversubscription
The Remaining CoS Packet Flow
CoS Processing: Port- and Queue-Based MPCs
Trio Hashing and Load Balancing
Key Aspects of the Trio CoS Model
Trio CoS Processing Summary
Hierarchical CoS
The H-CoS Reference Model
Level 4: Queues
Level 3: IFL
Level 2: IFL-Sets
Level 1: IFD
Remaining
Interface Modes and Excess Bandwidth Sharing
Priority-Based Shaping
Fabric CoS
Control CoS on Host-Generated Traffic
H-CoS Summary
Trio Scheduling and Queuing
Scheduling Discipline
Scheduler Priority Levels
Scheduler Modes
H-CoS and Aggregated Ethernet Interfaces
Schedulers, Scheduler Maps, and TCPs
Trio Scheduling and Priority Summary

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319
320
323
330
331
334
334
339
344
348
349
350
352
355
358
362
362
368
384
386
387
392
393
393
395
403
421

423
430


MX Trio CoS Defaults
Four Forwarding Classes, but Only Two Queues
Default BA and Rewrite Marker Templates
MX Trio CoS Defaults Summary
Predicting Queue Throughput
Where to Start?
Trio CoS Proof-of-Concept Test Lab
Predicting Queue Throughput Summary
CoS Lab
Configure Unidirectional CoS
Verify Unidirectional CoS
Confirm Scheduling Behavior
Add H-CoS for Subscriber Access
Configure H-CoS
Verify H-CoS
Trio CoS Summary
Chapter Review Questions
Chapter Review Answers

430
431
432
434
434
435
437

451
451
453
473
494
508
512
516
529
529
532

6. MX Virtual Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537
What is Virtual Chassis?
MX-VC Terminology
MX-VC Use Case
MX-VC Requirements
MX-VC Architecture
MX-VC Interface Numbering
MX-VC Packet Walkthrough
Virtual Chassis Topology
Mastership Election
Summary
MX-VC Configuration
Chassis Serial Number
Member ID
R1 VCP Interface
Routing Engine Groups
Virtual Chassis Configuration
R2 VCP Interface

Virtual Chassis Verification
Revert to Standalone
Summary
VCP Interface Class of Service
VCP Traffic Encapsulation
VCP Class of Service Walkthrough

537
539
540
541
543
554
556
558
559
560
561
561
562
563
564
566
567
570
572
573
573
573
574

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Forwarding Classes
Schedulers
Classifiers
Rewrite Rules
Final Configuration
Verification
Summary
Chapter Review Questions
Chapter Review Answers

575
576
578
580
581
583
584
585
586

7. Trio Inline Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 589
What are Trio Inline Services?
J-Flow
J-Flow Evolution

Inline IPFIX Performance
Inline IPFIX Configuration
Inline IPFIX Verification
IPFIX Summary
Network Address Translation
Types of NAT
Services Inline Interface
Service Sets
Destination NAT Configuration
Network Address Translation Summary
Tunnel Services
Enabling Tunnel Services
Tunnel Services Case Study
Tunnel Services Summary
Port Mirroring
Port Mirror Case Study
Port Mirror Summary
Summary
Chapter Review Questions
Chapter Review Answers

589
590
591
591
592
599
601
601
601

603
604
618
621
621
622
623
632
632
634
639
640
640
641

8. Multi-Chassis Link Aggregation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 643
Multi-Chassis Link Aggregation
MC-LAG State Overview
MC-LAG Family Support
Multi-Chassis Link Aggregation versus MX Virtual-Chassis
MC-LAG Summary
Inter-Chassis Control Protocol
ICCP Hierarchy
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643
645
646

647
648
648
649


ICCP Topology Guidelines
How to Configure ICCP
ICCP Configuration Guidelines
ICCP Split Brain
ICCP Summary
MC-LAG Modes
Active-Standby
Active-Active
MC-LAG Modes Summary
Case Study
Logical Interfaces and Loopback Addressing
Layer 2
Layer 3
MC-LAG Configuration
Connectivity Verification
Case Study Summary
Summary
Chapter Review Questions
Chapter Review Answers

652
652
659
664

665
665
666
668
673
673
675
676
689
695
707
716
716
717
718

9. Junos High Availability on MX Routers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 721
Junos High-Availability Feature Overview
Graceful Routing Engine Switchover
The GRES Process
Configure GRES
GRES Summary
Graceful Restart
GR Shortcomings
Graceful Restart Operation: OSPF
Graceful Restart and other Routing Protocols
Configure and Verify OSPF GR
Graceful Restart Summary
Nonstop Routing and Bridging
Replication, the Magic That Keeps Protocols Running

Nonstop Bridging
Current NSR/NSB Support
This NSR Thing Sounds Cool; So What Can Go Wrong?
Configure NSR and NSB
Verify NSR and NSB
NSR Summary
In-Service Software Upgrades
ISSU Operation
ISSU Layer 3 Protocol Support

721
723
723
728
740
740
741
741
747
751
761
761
762
767
769
776
783
785
813
814

814
819

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ISSU Layer 2 Support
MX MIC/MPC ISSU Support
ISSU: A Double-Edged Knife
ISSU Summary
ISSU Lab
Verify ISSU Readiness
Perform an ISSU
Summary
Chapter Review Questions
Chapter Review Answers

819
820
820
823
823
825
827
834
834
836

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 839

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About the Authors

Douglas Richard Hanks, Jr. is a Data Center Architect with Juniper Networks and
focuses on solution architecture. Previously, he was a Senior Systems Engineer with
Juniper Networks, supporting large enterprise accounts such as Chevron, HP, and
Zynga. He is certified with Juniper Networks as JNCIE-ENT #213 and JNCIE-SP
#875. Douglas’ interests are network engineering and architecture for enterprise and
service provider technologies. He is the author of several Day One books published by
Juniper Networks Books. Douglas is also the cofounder of the Bay Area Juniper Users
Group (BAJUG). When he isn’t busy with networking, Douglas enjoys computer programming, photography, and Arduino hacking. Douglas can be reached at
or on Twitter @douglashanksjr.
Harry Reynolds has over 30 years of experience in the networking industry, with the
last 20 years focused on LANs and LAN interconnection. He is CCIE # 4977 and JNCIE
# 3 and also holds various other industry and teaching certifications. Harry was a
contributing author to Juniper Network Complete Reference (McGraw-Hill) and wrote
the JNCIE and JNCIP Study Guides (Sybex Books). He coauthored Junos Enterprise
Routing and Junos Enterprise Switching (O’Reilly). Prior to joining Juniper, Harry served
in the US Navy as an Avionics Technician, worked for equipment manufacturer Micom
Systems, and spent much time developing and presenting hands-on technical training
curricula targeted to both enterprise and service provider needs. Harry has developed
and presented internetworking classes for organizations such as American Institute,
American Research Group, Hill Associates, and Data Training Resources. Currently,
Harry performs Customer Specific Testing that simulates one of the nation's largest

private IP backbones at multidimensional scale. When the testing and writing is done
(a rare event, to be sure), Harry can be found in his backyard metal shop trying to make
Japanese-style blades.

About the Lead Technical Reviewers
Stefan Fouant is a Technical Trainer and JNCP Proctor at Juniper Networks with over
15 years of experience in the networking industry. His first exposure to Junos was with
Junos 3.4 on the original M40 back in 1998, and it has been a love affair ever since. His

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background includes launching an industry-first DDoS Mitigation and Detection service at Verizon Business, as well as building customized solutions for various missioncritical networks. He holds several patents in the areas of DDoS Detection and Mitigation, as well as many industry certifications including CISSP, JNCIE-SP, JNCIEENT, and JNCIE-SEC.
Artur Makutunowicz has over five years of experience in Information Technology.
He was a Technical Team Leader at a large Juniper Elite partner. His main areas of
interest are Service Provider technologies, network device architecture, and Software
Defined Networking (SDN). He was awarded with JNCIE-ENT #297 certification.
Artur was also a technical reviewer of Day One: Scaling Beyond a Single Juniper SRX in
the Data Center, published by Juniper Networks Books. He is currently an independent
contractor and can be reached at

About the Technical Reviewers
Many Junos engineers reviewed this book. They are, in the authors’ opinion, some of
smartest and most capable networking people around. They include but are not limited
to: Kannan Kothandaraman, Ramesh Prabagaran, Dogu Narin, Russell Gerald Kelly,
Rohit Puri, Sunesh Rustagi, Ajay Gaonkar, Shiva Shenoy, Massimo Magnani, Eswaran
Srinivasan, Nitin Kumar, Ariful Huq, Nayan Patel, Deepak Ojha, Ramasamy Ramanathan, Brandon Bennett, Scott Mackie, Sergio Danelli, Qi-Zhong Cao, Eric Cheung
Young Sen, Richard Fairclough, Madhu Kopalle, Jarek Sawczuk, Philip Seavey, and

Amy Buchanan.

Proof of Concept Laboratory
In addition, the authors humbly thank the POC Lab in Sunnyvale, California, where
the test bed for this book was cared for and fed by Roberto Hernandez, Ridha Hamidi,
and Matt Bianchi. Without access to test equipment, this book would have been impossible.

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Preface

One of the most popular routers in the enterprise and service provider market is the
Juniper MX Series. The industry is moving to high-speed, high port-density Ethernetbased routers, and the Juniper MX was designed from the ground up to solve these
challenges.
This book is going to show you, step-by-step, how to build a better network using the
Juniper MX—it’s such a versatile platform that it can be placed in the core, aggregation,
or edge of any type of network and provide instant value. The Juniper MX was designed
to be a network virtualization beast. You can virtualize the physical interfaces, logical
interfaces, control plane, data plane, network services, and even have virtualized services span several Juniper MX routers. What was traditionally done with an entire army
of routers can now be consolidated and virtualized into a single Juniper MX router.

No Apologies
We’re avid readers of technology books, and we always get a bit giddy when a new
book is released because we can’t wait to read it and learn more about a specific technology. However, one trend we have noticed is that every networking book tends to
regurgitate the basics over and over. There are only so many times you can force yourself
to read about spanning tree, the split horizon rule, or OSPF LSA types. One of the goals
of this book is to introduce new and fresh content that hasn’t been published before.

There was a conscious decision made between the authors to keep the technical quality
of this book very high; this created a constant debate whether or not to include primer
or introductory material in the book to help refresh a reader’s memory with certain
technologies and networking features. In short, here’s what we decided:
Spanning Tree
There’s a large chapter on bridging, VLAN mapping, IRB, and virtual switches. A
logical choice would be to include the spanning tree protocol in this chapter.
However, spanning tree has been around forever and quite frankly there’s nothing
special or interesting about it. Spanning tree is covered in great detail in every
JNCIA and CCNA book on the market. If you want to learn more about spanning

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tree check out Junos Enterprise Switching by O’Reilly or CCNA ICND2 Official
Exam and Certification Guide, Second Edition by Cisco Press.
Basic Firewall Filters
We decided to skip the basic firewall filter introduction and jump right into the
advanced filtering and policing that’s available on the Juniper MX. Hierarchical
policers, two-rate three-color policers, and cascading firewall filters are much more
interesting.
Class of Service
This was a difficult decision because Chapter 5 is over 170 pages of advanced
hierarchal class of service. Adding another 50 pages of class of service basics would
have exceeded page count constraints and provided no additional value. If you
would like to learn more about basic class of service check out QoS-Enabled Networks by Wiley, Junos Enterprise Routing, Second Edition by O’Reilly, or Juniper
Networks Certified Internet Expert Study Guide by Juniper Networks.
Routing Protocols

There are various routing protocols such as OSPF and IS-IS used throughout this
book in case studies. No introduction chapters are included for IS-IS or OSPF, and
it’s assumed that you are already familiar with these routing protocols. If you want
to learn more about OSPF or IS-IS, check out the Junos Enterprise Routing, Second
Edition by O’Reilly or Juniper Networks Certified Internet Expert Study Guide by
Juniper Networks.
Virtual Chassis
This was an interesting problem to solve. On one hand, virtual chassis was covered
indepth in the book Junos Enterprise Switching by O’Reilly, but on the other hand
there are many caveats and features that are only available on the Juniper MX. It
was decided to provide enough content in the introduction that a new user could
grasp the concepts, but someone already familiar with virtual chassis wouldn’t
become frustrated. Chapter 6 specifically focuses on the technical prowess of virtual chassis and the Juniper MX implementation of virtual chassis.
After many hours of debate over Skype, it was decided that we should defer to other
books when it comes to introductory material and keep the content of this book at an
expert level. We expect that most of our readers already have their JNCIE or CCIE (or
are well on their way) and will enjoy the technical quality of this book. For beginning
readers, we want to share an existing list of books that are widely respected within the
networking community:
Junos Enterprise Routing, Second Edition, O’Reilly
Junos Enterprise Switching, O’Reilly
Junos Cookbook, O’Reilly
Junos Security, O’Reilly
Junos High Availability, O’Reilly
QoS-Enabled Networks, Wiley & Sons

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MPLS-Enabled Applications, Third Edition, Wiley & Sons
Network Mergers and Migrations, Wiley
Juniper Networks Certified Internet Expert, Juniper Networks
Juniper Networks Certified Internet Professional, Juniper Networks
Juniper Networks Certified Internet Specialist, Juniper Networks
Juniper Networks Certified Internet Associate, Juniper Networks
CCIE Routing and Switching, Fourth Edition, Cisco Press
Routing TCP/IP, Volumes I and II, Cisco Press
OSPF and IS-IS, Addison-Wesley
OSPF: Anatomy of an Internet Routing Protocol, Addison-Wesley
The Art of Computer Programming, Addison-Wesley
TCP/IP Illustrated, Volumes 1, 2, and 3, Addison-Wesley
UNIX Network Programming, Volumes 1 and 2, Prentice Hall PTR
Network Algorithmics: An Interdisciplinary Approach to Designing Fast Networked
Devices, Morgan Kaufmann

Book Topology
Using the same methodology found in the JNCIP-M and JNCIE-M Study Guides, this
book will use a master topology and each chapter will use a subset of the devices that
are needed to illustrate features and case studies. The master topology is quite extensive
and includes four Juniper MX240s, two EX4500s, two EX4200s, and various port testers which can generate traffic and emulate peering and transit links. The topology is
broken into three major pieces:
Data Center 1
The left side of the topology represents Data Center 1. The devices include W1,
W2, S1, S2, R1, R2, P1, and T2. The address space can be summarized as
10.0.0.0/14.
Data Center 2
The right side of the topology represents Data Center 2. It’s common for networks
to have more than one data center, so it made sense to create a master topology

that closely resembles a real production network. The devices include W3, W4,
S3, S4, R3, R4, P2, and T2.
The Core
The core is really just a subset of the two data centers combined. Typically when
interconnecting data centers a full mesh of WAN links aren’t cost effective, so we
decided to only use a pair of links between Data Center 1 and Data Center 2.
For the sake of clarity and readability, the master topology has been broken into five
figures, Figure P-1 through Figure P-5: Interface Names, Aggregate Ethernet Assignments, Layer 2, IPv4 Addressing, and IPv6 Addressing. The breakdown and configuration of the equipment is as follows:

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W1: Web Server 1. This is a tester port that’s able to generate traffic.
W2: Web Server 2. This is a tester port that’s able to generate traffic.
S1: Access Switch 1. This is a Juniper EX4500 providing both Layer 2 and Layer 3
access.
S2: Access Switch 2. This is a Juniper EX4500 providing both Layer 2 and Layer 3
access.
R1: Core Router/WAN Router 1. Juniper MX240 with a MPC2 Enhanced Queuing
line card.
R2: Core Router/WAN Router 2. Juniper MX240 with a MPC2 Enhanced Queuing
line card.
R3: Core Router/WAN Router 3. Juniper MX240 with a MPC2 line card.
R4: Core Router/WAN Router 4. Juniper MX240 with a MPC2 Queuing line card.
S3: Access Switch 3. Juniper EX4200 providing both Layer 2 and Layer 3 access.
S4: Access Switch 4. Juniper EX4200 providing both Layer 2 and Layer 3 access.
W3: Web Server 3. This is a tester port that’s able to generate traffic.
W4: Web Server 4. This is a tester port that’s able to generate traffic.

P1: Peering Router 1. This is a tester port that’s able to generate traffic.
P2: Peering Router 2. This is a tester port that’s able to generate traffic.
T1: Transit Router 1. This is a tester port that’s able to generate traffic.
T2: Transit Router 2. This is a tester port that’s able to generate traffic.

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Interface Names

Figure P-1. Master topology: Interface names
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Aggregate Ethernet Assignments

Figure P-2. Master topology: Aggregate ethernet assignments
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Layer 2

Figure P-3. Master topology: Layer 2
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