Interconnecting
Data Centers Using VPLS
Nash Darukhanawalla, CCIE No. 10332
Patrice Bellagamba
Cisco Press
800 East 96th Street Indianapolis, IN 46240Contents
Introduction xv
Chapter 1 Data Center Layer 2 Interconnect 1
Overview of High-Availability Clusters 2 Public Network Attachment 3 Private Network Attachment 3
Data Center Interconnect: Legacy Deployment Models 4 Problems Associated with Extended Layer 2 Networks 5 Summary 7
Chapter 2 Appraising Virtual Private LAN Service 9
VPN Technology Considerations 9 Layer 3 Virtual Private Networks 10 Layer 2 Virtual Private Networks 10 VPLS Overview 11
Understanding Pseudowires 14
VPLS to Scale STP Domain for Layer 2 Interconnection 15 H-VPLS Considerations 17
EEM 18 MPLS 19
Label Switching Functions 19 MPLS LDP 20
MPLS LDP Targeted Session 20 Limit LDP Label Allocation 21 MPLS LDP-IGP Synchronization 21 MPLS LDP TCP "Pak Priority" 21 MPLS LDP Session Protection 22
Summary 22
Chapter 3 High Availability for Extended Layer 2 Networks 23
MTU Evaluation for Intersite Transport 23 Core Routing 25
Mixed MPLS/IP Core 26
Different IGP for IP Core and MPLS 27 Same IGP for IP Core and MPLS 27
Pure MPLS Core 28 Pure IP Core 30
ix
Convergence Optimization 32 Key Convergence Elements 33 Failure Detection and Tuning 33
IP Event Dampening 34 BFD 35
Link Debounce Timer 37 Carrier-Delay Timer 38
Alternate Route Computation 40 Summary 42
Chapter 4 MPLS Traffic Engineering 43
Understanding MPLS-TE 43 Fast Reroute 44 Load Repartition over the Core 45
Load Repartition over a Parallel-Links Bundle 45
Implementing MPLS-TE for Traffic Repartition over Parallel Links 46 Enable ТЕ 47
Create MPLS-TE Tunnels and Map Each VFI to a Tunnel LSP 48 Explicit-Path Option 48
Adding FRR to Explicit Option 50
Affinity Option 52
Adding FRR to Affinity Option 52
Summary 53
Chapter 5 Data Center Interconnect: Architecture Alternatives 55
Ensuring a Loop-Free Global Topology: Two Primary Solution Models 55 N-PE Using MST for Access to VPLS 5 6
N-PE Using ICCP Emulation for Access to VPLS 56
Data Center Interconnect Design Alternatives: Summary and Comparison 57
Chapter 6 Case Studies for Data Center Interconnect 61
Case Study 1: Large Government Organization 61 Challenges 61
Solution 62
Case Study 2: Large Outsourcer for Server Migration and Clustering 65 Challenges 65
Solution 65 Summary 68
Chapter 7 Data Center Multilayer Infrastructure Design 69
Network Staging for Design Validation 71 Hardware and Software 72
Convergence Tests 73
Traffic Flow 73 Traffic Rate 73 Traffic Profile 74
Summary 76
Chapter 8 MST-Based Deployment Models 77
MST in N-PE: MST Option la 77
Implementing MST in N-PE: MST Option la Design 80 Convergence Tests 100
Cluster Server Tests 103
VPLS with N-PE Redundancy Using RPVST with Isolated MST in N-PE: MST Option lb 106
EEM Scripting to Complement Isolated MST Solution 109 Implementing RPVST in a Data Center with Isolated MST
in N-PE (MST Option lb) Design 110 Convergence Tests 130
Cluster Server Tests 134 Summary 138
Chapter 9 EEM-Based Deployment Models 139
N-PE Redundancy Using the Semaphore Protocol: Overview 139 Semaphore Definition 141
Semaphore Theory Application 142
N-PE Redundancy Using Semaphore Protocol: Details 142 VPLS PWs in Normal Mode 142
Primary N-PE Failure 145
Primary N-PE Recovers After the Failure 145 Implementing a Semaphore 146
EEM / Semaphore Scripts 147 Naming Conventions 148
Loopback Definitions 148 Node Definitions 149
VPLS with N-PE Redundancy Using EEM Semaphore: EEM Option 2 150
xi Control Plane 151 Data Plane 151 Theory of Operation 151 Normal Mode 151 Failure Conditions 152
Primary N-PE Node Failure 153
Primary N-PE Node Recovers After the Failure 154
N-PE Routers: Hardware and Software 154 Implementing VPLS with N-PE Redundancy Using
EEM Semaphore Design 154 Convergence Tests 168
Cluster Server Tests 172
H-VPLS with N-PE Redundancy Using EEM Semaphore: EEM Option 3 176
Control Plane 179 Data Plane 179
Theory of Operation 179
Normal Mode 179
Primary N-PE Node or Q-Link Failure 180
Primary N-PE Node or Q-Link Recovers After the Failure 181
N-PE Routers: Hardware and Software 182
Implementing H-VPLS with N-PE Redundancy Using EEM Semaphore Design 182
Convergence Tests 195 Server Cluster Tests 199
Multidomain H-VPLS with N-PE Redundancy: EEM Option 4a 201 Control Plane 203
Data Plane 203
Theory of Operation 204
Normal Mode 204
Primary N-PE Node or Q-Link Failure 204
Primary N-PE Node or Q-Link Recovery After the Failure 205
N-PE Routers: Hardware and Software 207
Implementing Multidomain H-VPLS with N-PE Redundancy Using EEM Semaphore Design 207
Convergence Tests 217 Server Cluster Tests 221
Multidomain H-VPLS with Dedicated U-PE: EEM Option 4b 227
Multidomain H-VPLS with Multichassis EtherChannel: EEM Option 5a 227 Solution Positioning 230
Multidomain H-VPLS with MEC and VLAN Load Balancing: EEM Option 5b 230
Control Plane 233 Data Plane 233
Theory of Operation 233
Normal Mode 233
Primary N-PE Node Failure 234
Primary N-P Node Recovers After the Failure 235
N-PE Routers: Hardware and Software 236 Implementing EEM Option 5b 237 Convergence Tests 252
Server Tests 259
Multidomain H-VPLS with MEC and VLAN Load Balancing: PWs on Active and Standby VPLS Nodes in Up/Up State: EEM Option 5 c 262
N-PE Routers: Hardware and Software 264 Configuration Summary 265
Convergence Tests 270 Summary 275
Chapter 10 GRE-Based Deployment Model 277
Key Configuration Steps for VPLSoGRE-Based Solutions 279 VPLSoGRE with N-PE Redundancy Using EEM Semaphore 282
Convergence Tests 284 Cluster Server Tests 286
VPLSoGRE: Multidomain with H-VPLS Solution 291 Convergence and Cluster Server Tests 296
Cluster Server Tests 298 Summary 302
Chapter 11 Additional Data Center Interconnect Design Considerations 303
Multicast Deployment in a Layer 2 Environment 303 Multicast at Layer 2 304
Tuning the IGMP Query Interval 304
xiii
Routing Design 306
QinQ MAC Overlapping 307 Storm Control 310
L2 Control-Plane Packet Storm Toward N-PE 311 L2 Broadcast and Multicast Packet Storm 312 L2 Known Unicast Packet Storm 313
L2 Unknown Unicast Packet Storm 314 QoS Considerations 315
Stateful Switchover Considerations 318 IGP (OSPF) Cost 318
Router ID Selection 319 Summary 319
Chapter 12 VPLS PE Redundancy Using Inter-Chassis Communication Protocol 321
Introducing ICCP 322
Interaction with AC Redundancy Mechanisms 324 Interaction with PW Redundancy Mechanisms 325 Configuring VPLS PE Redundancy Using ICCP 326 Summary 327
Chapter 13 Evolution of Data Center Interconnect 329
A Larger Problem to Solve 329
Networking Technology: Research Directions 330 Improving Legacy L2 Bridging 330
New Concepts in L2 Bridging 331
L2 Service over L3 Transport: MPLS or IP? Battle or Coexistence? 332 Summary 333
Glossary 335
