Introduction xxxii Chapter 1 Introduction to Congestion in Storage Networks 1 Types of Storage in a Data Center 1 Storage Protocols, Transports, and Networks 6 Storage Networks 21 Congestion in Storage Networks: An Overview 28 NVMe over Fabrics 43 Quality of Service (QoS) 46 Summary 51 References 52 Chapter 2 Understanding Congestion in Fibre Channel Fabrics 55 Fibre Channel Flow Control 55 Congestion Spreading in Fibre Channel Fabrics 67 Frame Flow Within a Fibre Channel Switch 86 The Effects of Bit Errors on Congestion 92 B2B Credit Loss and Recovery 112 Fibre Channel Counters Summary 123 Summary 127 References 127 Chapter 3 Detecting Congestion in Fibre Channel Fabrics 129 Congestion Detection Workflow 129 Congestion Detection Metrics 135 Congestion Detection Metrics on Cisco MDS Switches 137 Automatic Alerting 168 Detecting Congestion Using Remote Monitoring Platforms 177 Detecting Congestion Due to Slow Drain and Overutilization 192 Slow Drain and Overutilization at the Same Time 194 Detecting Congestion on long-distance links 195 Summary 195 References 196 Chapter 4 Troubleshooting Congestion in Fibre Channel Fabrics 199 Troubleshooting Methodology and Workflow 199 Hints and Tips for Troubleshooting Congestion 214 Cisco MDS NX-OS Commands for Troubleshooting Congestion 219 Case Study 1: Finding Congestion Culprits and Victims in a Single-Switch Fabric 242 Case Study 2: Credit Loss Recovery Causing Frame Drops 271 Case Study 3: Overutilization on a Single Device Causing Massive Congestion Problems 297 Case Study 4: Long-Distance ISLs Causing Congestion 323 Summary 336 References 337 Chapter 5 Solving Congestion with Storage I/O Performance Monitoring 339 Why Monitor Storage I/O Performance? 339 How and Where to Monitor Storage I/O Performance 340 Cisco SAN Analytics Architecture 344 Understanding I/O Flows in a Storage Network 347 I/O Flow Metrics 350 I/O Operations and Network Traffic Patterns 358 Summary 379 References 379 Chapter 6 Preventing Congestion in Fibre Channel Fabrics 381 An Overview of Eliminating or Reducing Congestion 382 Link Capacity 386 Congestion Recovery by Disconnecting the Culprit Device 387 Congestion Recovery by Dropping Frames 388 Traffic Segregation 398 Congestion Prevention Using Rate Limiters on Storage Arrays 433 Congestion Prevention Using Dynamic Ingress Rate Limiting on Switches 436 Preventing Congestion by Notifying the End Devices 457 Network Design Considerations 469 Summary 475 References 476 Chapter 7 Congestion Management in Ethernet Storage Networks 479 Ethernet Flow Control 479 Understanding Congestion in Lossless Ethernet Networks 506 Detecting Congestion in Lossless Ethernet Networks 511 Troubleshooting Congestion in Lossless Ethernet Networks 534 Preventing Congestion in Lossless Ethernet Networks 547 Lossless Traffic with VXLAN 565 Summary 569 References 570 Chapter 8 Congestion Management in TCP Storage Networks 573 Understanding Congestion in TCP Storage Networks 574 Storage I/O Performance Monitoring 587 Preventing Congestion in TCP Storage Networks 597 Detecting Congestion in TCP Storage Networks 615 Troubleshooting Congestion in TCP Storage Networks 625 iSCSI and NVMe/TCP in a Lossless Network 630 iSCSI and NVMe/TCP with VXLAN 631 Fibre Channel over TCP/IP (FCIP) 631 Modified TCP Implementations 637 Summary 638 References 639 Chapter 9 Congestion Management in Cisco UCS Servers 641 Cisco UCS Architecture 641 Understanding Congestion in a UCS Domain 644 Detecting Congestion in a UCS Domain 645 The UCS Traffic Monitoring (UTM) App 648 Summary 668 References 669 9780137887231, TOC, 1/17/2024.
Detecting, Troubleshooting, and Preventing Congestion in Storage Networks