Interconnecting Data Centers Using VPLS Nash Darukhanawalla, CCIE No. 10332 Patrice Bellagamba Cisco Press 800 East 96th Street Indianapolis, IN 46240
viii Interconnecting Data Centers Using VPLS Contents 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
x Interconnecting Data Centers Using VPLS 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
xii Interconnecting Data Centers Using VPLS 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 Spanning Tree, HSRP, and Service Module Design 306
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 Index 339