Today's rapidly changing technology offers increasingly complex challenges to the network administrator, MIS director and others who are responsible for the overall health of the network. This Network Maintenance and Troubleshooting Guide picks up where other network manuals and texts leave off. It addresses the areas of how to anticipate and prevent problems, how to solve problems, how to operate a healthy network and how to troubleshoot. Network Maintenance and Troubleshooting Guide also provides basic technical and troubleshooting information about cable testing, Ethernet and Token Ring networks and additional information about Novell's IPX(R) protocol and TCP/IP. Examples are shown as either diagrams and tables, or screen captures from Fluke instruments. Network professionals will appreciate the guide's "real world" orientation toward solving network crises quickly, by guiding readers to solutions for restoration of end to end data delivery as quickly as possible. The network novice will learn from the simplified descriptions about networking technology in the Appendices.
Broken down into routable and nonroutable protocols, this handbook focuses on specific and potentially problematic issues common to each network type. As an aid for professionals in the field of Internet-working, it helps them make more intelligent, time- and cost-effective decisions for their environment.
Over the years, thousands of tools have been developed for debugging TCP/IP networks. They range from very specialized tools that do one particular task, to generalized suites that do just about everything except replace bad Ethernet cables. Even better, many of them are absolutely free. There's only one problem: who has time to track them all down, sort through them for the best ones for a particular purpose, or figure out how to use them?Network Troubleshooting Tools does the work for you--by describing the best of the freely available tools for debugging and troubleshooting. You can start with a lesser-known version of ping that diagnoses connectivity problems, or take on a much more comprehensive program like MRTG for graphing traffic through network interfaces. There's tkined for mapping and automatically monitoring networks, and Ethereal for capturing packets and debugging low-level problems.This book isn't just about the tools available for troubleshooting common network problems. It also outlines a systematic approach to network troubleshooting: how to document your network so you know how it behaves under normal conditions, and how to think about problems when they arise, so you can solve them more effectively.The topics covered in this book include: Understanding your network Connectivity testing Evaluating the path between two network nodes Tools for capturing packets Tools for network discovery and mapping Tools for working with SNMP Performance monitoring Testing application layer protocols Software sources If you're involved with network operations, this book will save you time, money, and needless experimentation.
The situation is dire for British forces in the Mediterranean, and Commander Nick Everard and his son Jack find themselves in the midst of chaos. Aboard separate ships, the Everards are part of a flotilla patrolling the Aegean. There they face the terrifying bomber attacks of German Stukas as they struggle to save as many of the evacuating troops as possible. But when the order comes for one last lift from Crete, the decimated flotilla must make a suicide run—and only a miracle can save them!
Helping users efficiently analyze current and potential network security problems and identifying viable solutions, this reference is organized in a modular fashion so readers can flip directly to the needed information. Case studies serve to illustrate how problems are resolved in the real world.
A complete resource for assessing, auditing, analyzing, and evaluating any network environment With "Network Consultants Handbook, you will Learn from network audit and evaluation guidelines that aid in data gathering and analysis of network environments Work with tables and calculations that help provide near-real-time answers to internetworking issues and challenges Learn network diagramming tips that aid consultants and engineers in preparing consistent drawings for in-house documentation Discover how specific internetworking technologies fit into a design to create a networking solution for your customer Network consultants and engineers in today's industry continually face the challenge of assessing, auditing, and reviewing existing networks. Documenting, reviewing, and analyzing these changes in a customer's network is more challenging today than in the past, partly because of the explosive growth of converged applications and the Internet. Consultants and engineers often reinvent the wheel to gather and analyze relevant network information, particularly when examining a client's network while having little or no background information. "Network Consultants Handbook is a complete resource for assessing, auditing, analyzing, and evaluating any network environment. Intended for anyone who designs, manages, sells, administrates, or desires to understand various internetworking technologies, "Network Consultants Handbook demonstrates where and how to gather relevant information and how to analyze and document this information. Technology overviews peel away each layer of the network to provide a complete assessment. This book prepares you with form templates to completeduring a network audit, necessary device commands to aid in obtaining necessary information, and consistent forms to aid in documentation. Networks are like snowflakes: No two are alike. This is the challenge that network consultants, engineers, managers, designers, and anyone else involved with networks must face every day. Network Consultants Handbook provides the resources you need to evaluate and design networks, either as a desktop reference resource or in the field where the tables and calculations help provide near-real-time answers to internetworking issues and challenges. Companion Web Site The companion Web site for the book contains fully downloadable versions of the data gathering and analysis templates. These templates offer an easy-to-complete solution to gathering the data you need to complete your analysis of network environments. This book is part of the Cisco Press Networking Technologies Series, which offers networking professionals valuable information for constructing efficient networks, understanding new technologies, and building successful careers.
The definitive guide to troubleshooting today’s complex BGP networks This is today’s best single source for the techniques you need to troubleshoot BGP issues in modern Cisco IOS, IOS XR, and NxOS environments. BGP has expanded from being an Internet routing protocol and provides a scalable control plane for a variety of technologies, including MPLS VPNs and VXLAN. Bringing together content previously spread across multiple sources, Troubleshooting BGP describes BGP functions in today’s blended service provider and enterprise environments. Two expert authors emphasize the BGP-related issues you’re most likely to encounter in real-world deployments, including problems that have caused massive network outages. They fully address convergence and scalability, as well as common concerns such as BGP slow peer, RT constraint filtering, and missing BGP routes. For each issue, key concepts are presented, along with basic configuration, detailed troubleshooting methods, and clear illustrations. Wherever appropriate, OS-specific behaviors are described and analyzed. Troubleshooting BGP is an indispensable technical resource for all consultants, system/support engineers, and operations professionals working with BGP in even the largest, most complex environments. · Quickly review the BGP protocol, configuration, and commonly used features · Master generic troubleshooting methodologies that are relevant to BGP networks · Troubleshoot BGP peering issues, flapping peers, and dynamic BGP peering · Resolve issues related to BGP route installation, path selection, or route policies · Avoid and fix convergence problems · Address platform issues such as high CPU or memory usage · Scale BGP using route reflectors, diverse paths, and other advanced features · Solve problems with BGP edge architectures, multihoming, and load balancing · Secure BGP inter-domain routing with RPKI · Mitigate DDoS attacks with RTBH and BGP Flowspec · Understand common BGP problems with MPLS Layer 3 or Layer 2 VPN services · Troubleshoot IPv6 BGP for service providers, including 6PE and 6VPE · Overcome problems with VXLAN BGP EVPN data center deployments · Fully leverage BGP High Availability features, including GR, NSR, and BFD · Use new BGP enhancements for link-state distribution or tunnel setup This book is part of the Networking Technology Series from Cisco Press, which offers networking professionals valuable information for constructing efficient networks, understanding new technologies, and building successful careers.
Identify, capture and resolve common issues faced by Red Hat Enterprise Linux administrators using best practices and advanced troubleshooting techniques About This Book Develop a strong understanding of the base tools available within Red Hat Enterprise Linux (RHEL) and how to utilize these tools to troubleshoot and resolve real-world issues Gain hidden tips and techniques to help you quickly detect the reason for poor network/storage performance Troubleshoot your RHEL to isolate problems using this example-oriented guide full of real-world solutions Who This Book Is For If you have a basic knowledge of Linux from administration or consultant experience and wish to add to your Red Hat Enterprise Linux troubleshooting skills, then this book is ideal for you. The ability to navigate and use basic Linux commands is expected. What You Will Learn Identify issues that need rapid resolution against long term root cause analysis Discover commands for testing network connectivity such as telnet, netstat, ping, ip and curl Spot performance issues with commands such as top, ps, free, iostat, and vmstat Use tcpdump for traffic analysis Repair a degraded file system and rebuild a software raid Identify and troubleshoot hardware issues using dmesg Troubleshoot custom applications with strace and knowledge of Linux resource limitations In Detail Red Hat Enterprise Linux is an operating system that allows you to modernize your infrastructure, boost efficiency through virtualization, and finally prepare your data center for an open, hybrid cloud IT architecture. It provides the stability to take on today's challenges and the flexibility to adapt to tomorrow's demands. In this book, you begin with simple troubleshooting best practices and get an overview of the Linux commands used for troubleshooting. The book will cover the troubleshooting methods for web applications and services such as Apache and MySQL. Then, you will learn to identify system performance bottlenecks and troubleshoot network issues; all while learning about vital troubleshooting steps such as understanding the problem statement, establishing a hypothesis, and understanding trial, error, and documentation. Next, the book will show you how to capture and analyze network traffic, use advanced system troubleshooting tools such as strace, tcpdump & dmesg, and discover common issues with system defaults. Finally, the book will take you through a detailed root cause analysis of an unexpected reboot where you will learn to recover a downed system. Style and approach This is an easy-to-follow guide packed with examples of real-world core Linux concepts. All the topics are presented in detail while you're performing the actual troubleshooting steps.
Troubleshooting and Maintaining Cisco IP Networks (TSHOOT) Foundation Learning Guide is a Cisco authorized, self-paced learning tool for CCNP preparation. This book educates network professionals on how to maintain and monitor network performance, troubleshoot multi protocol system networks, and troubleshoot Cisco device hardening issues.
CD-ROM contains: Internet related RFCs -- Internet modem technology reference -- Case study on firewalls and data communications -- Internetworking troubleshooting reference -- glossary and acronym list.
