Cisco router software crash

All Community This category This board. Software-forced crash. Labels: Other Networking. Core Issue A software-forced crash occurs when the router detects a severe, unrecoverable error and reloads itself to prevent the sending of corrupted data. Resolution If you have the output of a show stacks or show tech-support command from your Cisco device, you can use the Output Interpreter to display potential issues and fixes.

Tags: crash. Latest Contents. Created by sherif1 on AM. I need to achieve three g Created by Umesh Prajapati on AM. Need advise on connecting the fiber cable between two switch Check out the latest Insider stories here. More from the IDG Network. A Cisco router crash is when the system detects an unrecoverable error and restarts itself. A Cisco router crash can be caused by software problems, hardware problems, or both. Important information about the crash is lost if the router is reloaded after the crash , such as from the power-cycle or issuing the reload command.

Find out the type of crash by issuing a show version command. On the router, configure this:. Caution: Please do not manually reload or power-cycle the router before you collect the above information, if possible, as this can cause important information to be lost that is needed to determine the root cause of the problem. Contents Introduction. Introduction This document explains the most frequent causes of software-forced crashes, and describes the information you must collect in order to troubleshoot.

Prerequisites Requirements Readers of this document should have knowledge of these topics: How to Troubleshoot Router Crashes. Components Used This document is not restricted to specific software and hardware versions. Conventions For more information on document conventions, refer to the Cisco Technical Tips Conventions.

If you have not power-cycled or manually reloaded the router, output from the show version command displays this: Router uptime is 2 days, 21 hours, 30 minutes System restarted by error - Software-forced crash , PC 0xEF90 at edt System image file is "flash:cis-l. Possible Causes This table explains the possible reasons for software-forced crashes: Reason Explanation Watchdog timeouts The processor uses timers to avoid infinite loops, and causes the router to stop responding.

In normal operation, the CPU resets those timers at regular intervals. Failure to do so results in a system reload. Watchdog timeouts that are reported as software-forced crashes are software-related. Refer to Troubleshooting Watchdog Timeouts for information about other types of watchdog timeouts.

The system was stuck in a loop before the reload. Therefore, the stack trace is not necessarily relevant. In this case, the event is reported as a software-forced crash. In this case, you can load a new image onto the router to resolve the issue.

Other faults The errors that cause crashes are often detected by processor hardware, which automatically calls special error-handling code in the ROM monitor. The ROM monitor identifies the error, prints a message, saves information about the failure, and restarts the system. This document describes how to troubleshoot router crashes. A "system crash" is a situation where the system has detected an unrecoverable error and has restarted itself. The errors that cause crashes are typically detected by processor hardware, which automatically branches to special error handling code in the ROM monitor.

The ROM monitor identifies the error, prints a message, saves information about the failure, and restarts the system. The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared default configuration. If your network is live, make sure that you understand the potential impact of any command.

When the router crashes, it is extremely important to gather as much information as possible about the crash before you manually reload or power-cycle the router. All information about the crash, except that which has been successfully stored in the crashinfo file, is lost after a manual reload or power-cycle.

These outputs give some indication and information on the crash. If you have the output of a show version , show stacks , show context , or show tech support command from your Cisco device, you can use Cisco CLI Analyzer to display potential issues and fixes. The show version and show stacks commands provide you with output that gives you an indication of the type of the crash that occurred, such as bus error, or software forced crash.

You can also get crash type information from the crashinfo and show context commands. Follow these links to troubleshoot the specific type of crash your router experiences:. Address Error. Bus Error. Cache Error Exception. Format Error. Illegal Instruction. Illegal Opcode Exception.