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Cisco 12000 Series Routers

Troubleshooting TechNotes

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Basic Concepts and Maintenance
- "%Error opening tftp://255.255.255.255/network config" Error Message Prevention
  03/Aug/2006
- Back up and Restore Configuration Files
  03/Aug/2006
- Buffer Tuning for all Cisco Routers
  28/May/2008
- Capturing Text Output from Hyperterminal
  25/Jun/2008
- Characterizing and Tracing Packet Floods Using Cisco Routers
  27/May/2005
- Defining Strategies to Protect Against TCP SYN Denial of Service Attacks
  06/Jan/2006
- How to Protect Your Network Against the Nimda Virus
  06/Mar/2008
- How to Upgrade from ROMmon Using the Boot Image
  27/Jan/2006
- Implementing Access Lists on Cisco 12000 Series Internet Routers
  19/Feb/2007
- Maximum Number of Interfaces and Subinterfaces for Cisco IOS Platforms: IDB Limits
  24/Jun/2008
- Online Insertion and Removal (OIR) Support in Routers
  24/Jun/2008
- Performance Tuning Basics
  11/Jul/2007
- Prevent "Translating. domain server (255.255.255.255)" Messages after an Invalid Command is Entered on a Router
  02/Aug/2006
- Problems Caused by Simultaneous Access to Router NVRAM
  03/Aug/2006
- Reset a Cisco Router to Factory Default Settings
  02/Aug/2006
- TCP and UDP Small Servers
  01/Aug/2006
- Understand and Configure MDRR/WRED on the Cisco 12000 Series Internet Router
  06/Mar/2008
- Understanding Cisco Express Forwarding (CEF)
  17/Jan/2006
- Understanding Selective Packet Discard (SPD)
  07/Jul/2005
- Understanding the Booting Process on the Cisco 12000 Series Internet Router
  31/Aug/2006
- Understanding the Definition of bits per second (bits/sec) from the show interfaces Command Output
  01/Aug/2006
- Understanding the Ping and Traceroute Commands
  29/Nov/2006
- Use of the Configuration Register on All Cisco Routers
  03/Apr/2006
- Using Network-Based Application Recognition and ACLs for Blocking the "Code Red" Worm
  02/Aug/2006
Boot Failure Recovery and IOS Upgrade
- How to Choose a Cisco IOS Software Release
  29/Nov/2006
- How To Copy a System Image from One Device to Another
  02/Aug/2006
- ROMmon Recovery Procedure for the Cisco 7200, 7300, 7400, 7500, RSP7000, Catalyst 5500 RSM, uBR7100, uBR7200, uBR10000, and 12000 Series Routers
  30/Jan/2006
- Standard Break Key Sequence Combinations During Password Recovery
  02/Aug/2006
- TFTP Server Selection and Use
  02/Feb/2006
- Why Does My Router Lose Its Configuration During Reboot?
  25/Jun/2008
- Xmodem Console Download Procedure Using ROMmon
  01/Feb/2006
Cables and Specifications
- Auxiliary Port, Console Port, And Adapter Pinouts For Cisco 1000, 1600, 2500, 2600, And 3600 Series Routers
  27/Jan/2006
- CAB-X21 MT and CAB-X21 FC Serial Cable Specifications
  21/Nov/2006
- CAB-530 MT Serial Cable Specifications
  27/Jan/2006
- CAB-449 MT and CAB-449 FC EIA/TIA-449 Serial Cable Specifications
  30/Jan/2006
- CAB-232 MT and CAB-232 FC EIA/TIA-232 Serial Cable Specifications
  30/Jan/2006
- CAB-25AS-FDTE Adapter Technical Specifications
  30/Jan/2006
- CAB-25AS-MMOD Adapter Technical Specifications
  27/Jan/2006
- Cabling Guide for Console and AUX Ports
  03/Sep/2006
- Cisco Cable Product Numbers, Part Numbers, and Descriptions
  01/Aug/2006
- Ethernet AUI Port, Pinouts, and Cable Specifications
  30/Jan/2006
- Ethernet 100BaseTX and 10BaseT Cables: Guidelines and Specifications
  01/Aug/2006
- How to Connect a KG-84A to a Cisco Serial Interface
  01/Aug/2006
- Let's Connect:Your Serial Cable Guide
  01/Aug/2006
- 5-in-1 EIA/TIA-449 Assembly and Pinouts
  01/Aug/2006
- 5-in-1 EIA/TIA-232 Assembly and Pinouts
  04/Mar/2008
- 5-in-1 V.35 Assembly and Pinouts
  18/Dec/2007
- 5-in-1 X.21 Assembly and Pinouts
  04/Mar/2008
High CPU Utilization
- Dealing with mallocfail and High CPU Utilization Resulting From the "Code Red" Worm
  20/Jun/2008
- High CPU Utilization in Exec and Virtual Exec Processes
  30/Jun/2008
- The show processes Command
  15/Jan/2008
- Troubleshooting High CPU Utilization Due to Interrupts
  29/May/2008
- Troubleshooting High CPU Utilization due to Processes
  30/Jun/2008
- Troubleshooting High CPU Utilization in IP Input Process
  02/Aug/2006
- Troubleshooting High CPU Utilization on Cisco Routers
  30/Jun/2008
- What Causes %SYS-3-CPUHOG Messages?
  24/Jun/2008
- What Causes High CPU Utilization in LC Adj Updater process on a Cisco 12000 router ?
  07/Jul/2005
Router Architecture
- Cisco 12000 Series Internet Router Architecture: Chassis
  03/Apr/2006
- Cisco 12000 Series Internet Router Architecture: Line Card Design
  07/Jul/2005
- Cisco 12000 Series Internet Router Architecture: Maintenance Bus, Power Supplies and Blowers, and Alarm Cards
  17/Jan/2006
- Cisco 12000 Series Internet Router Architecture: Memory Details
  07/Jul/2005
- Cisco 12000 Series Internet Router Architecture: Packet Switching
  07/Jul/2005
- Cisco 12000 Series Internet Router Architecture: Route Processor
  07/Jul/2005
- Cisco 12000 Series Internet Router Architecture: Software Overview
  07/Jul/2005
- Cisco 12000 Series Internet Router Architecture: Switch Fabric
  07/Jul/2005
Troubleshooting Hardware
- Hardware Troubleshooting for Cisco 12000 Series Internet Router Line Card Failures
  07/Jul/2005
- Hardware Troubleshooting for the Cisco 12000 Series Internet Router
  15/Jan/2008
- Hardware Troubleshooting Index Page
  20/Oct/2006
- Processor Memory Parity Errors (PMPEs)
  31/Jan/2006
- SegV Exceptions
  31/Jul/2006
- Troubleshooting Buffer Leaks
  29/Nov/2006
- Troubleshooting Ethernet Collisions
  01/Aug/2006
- Troubleshooting Ignored Packets and No Memory Drops on the Cisco 12000 Series Internet Router
  07/Jul/2005
- Troubleshooting Input Drops on the Cisco 12000 Series Internet Router
  07/Jul/2005
- Troubleshooting Input Queue Drops and Output Queue Drops
  28/Nov/2006
- Troubleshooting Line Card Crashes on the Cisco 12000 Series Internet Router
  23/Apr/2007
- Troubleshooting Memory Problems
  28/Nov/2006
- Troubleshooting Spurious Accesses, Alignment Errors, and Spurious Interrupts
  02/Aug/2006
- Troubleshooting Watchdog Timeouts
  29/Nov/2006
Troubleshooting Router Hang and Router Crash
- Cisco 12000, 10000, 7600, and 7500 Series Routers: Troubleshooting IPC-3-NOBUFF Messages
  24/Jun/2008
- Creating Core Dumps
  24/Jun/2008
- Less Common Types of System Crashes
  29/Nov/2006
- Retrieving Information from the Crashinfo File
  01/Feb/2006
- Troubleshooting Bus Error Crashes
  29/Nov/2006
- Troubleshooting CEF-Related Error Messages
  24/Jun/2008
- Troubleshooting Fabric Ping Timeouts and Failures on the Cisco 12000 Series Internet Router
  15/Jan/2008
- Troubleshooting Router Crashes
  28/Nov/2006
- Troubleshooting Router Hangs
  02/Aug/2006
- Understanding Software-forced Crashes
  31/Jul/2006
- What Causes a Router To Be Restarted By the Abort or Trace Trap Commands
  29/Nov/2006
Miscellaneous
- Cisco 12000 Series Internet Router Parity Error Fault Tree
  29/Apr/2008
- Cisco 12000 Series Internet Router: GRP/ GRP-B to PRP Upgrade Procedure
  07/Jul/2005
- Configuring a Core Dump on a GSR Line Card
  02/Feb/2006
- Fiber Loss Budgets
  15/Jan/2008
- How To Read the Output of the Show Controller fia Command
  23/Jan/2008
- How to read the output of the show controller frfab | tofab queue commands on a Cisco 12000 Series Internet Router
  07/Jul/2005
- IFS-3-FS_STRUCT_ERROR: Data does not match expected internal representation
  15/Jan/2008
- Password Recovery Procedures
  17/Jan/2007
- PCMCIA Filesystem Compatibility Matrix and Filesystem Information
  10/Nov/2005
- Security Reference Information
  29/Jul/2003
- Upgrading Line Card Firmware on a Cisco 12000 Series Internet Router
  04/Dec/2006
- WRED and MDRR on the Cisco 12000 Series Internet Router with a Mix of Unicast, Multicast, and Voice Traffic Configuration Example
  07/Jul/2005