Troubleshooting Crashes And Hangs (Stack, Context, Frame, Sysret, Meminfo); Router Crashes; Router Hangs - Cisco 2800 Series Manual

How to Use the ROM Monitor—Typical Tasks
Sample Output for the set ROM Monitor Command
rommon 3 > set
What to Do Next
If you want to configure the router to load a specified image at the next system reload or power-cycle,
see the following documents:
•
•

Troubleshooting Crashes and Hangs (stack, context, frame, sysret, meminfo)

This section lists and describes some ROM monitor commands that can be used to troubleshoot router
crashes and hangs.
Most ROM monitor debug commands are functional only when the router crashes or hangs. If you enter
a debug command when crash information is not available, the following error message appears:
"xxx: kernel context state is invalid, can not proceed."
The ROM monitor commands in this section are all optional and can be entered in any order.

Router Crashes

A router or system crash is a situation in which the system detects an unrecoverable error and restarts
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. For detailed information
about troubleshooting crashes, see the
Software-forced Crashes

Router Hangs

A router or system hang is a situation in which the system does not respond to input at the console port
or to queries sent from the network, such as Telnet and Simple Network Management Protocol (SNMP).
Router hangs occur when:
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Using the ROM Monitor
24
Receiving c2801-is-mz.113-2.0.3.Q from 171.69.1.129 !!!!!.!!!!!!!!!!!!!!!!!!!.!!
File reception completed.
Copying file c2801-is-mz.113-2.0.3.Q to flash.
Erasing flash at 0x607c0000
program flash location 0x60440000
rommon 22 >
PS1=rommon ! >
IP_ADDRESS=172.18.16.76
IP_SUBNET_MASK=255.255.255.192
DEFAULT_GATEWAY=172.18.16.65
TFTP_SERVER=172.18.16.2
TFTP_FILE=anyname/rel22_Jan_16/c2801-i-mz
"Booting Commands" chapter of the Cisco IOS Configuration Fundamentals Command Reference
Cisco IOS Configuration Fundamentals and Network Management Configuration Guide
tech notes.
The console does not respond
Troubleshooting Router Crashes and Understanding
OL-5997-02