Which Cisco IOS diagnostics command can disrupt the operation of a router under high-load
conditions?
A.
debug all
B.
show running-config
C.
show processes cpu
D.
logging host ip address
Explanation:
Initial Troubleshooting
Once you notice any of the symptoms from the Symptoms of High CPU Utilization:
•Check for a possible security issue. Commonly, high CPU utilization is caused by a security
issue, such as a worm or virus operating in your network. This is especially likely to be the cause if
there have not been recent changes to the network. Usually, a configuration change, such as
adding additional lines to your access lists can mitigate the effects of this problem. Cisco Product
Security Advisories and Notices contains information on detection of the most likely causes and
specific workarounds.
For additional information, refer to:
o100 Questions and Answers about Internet Threats
oCisco Product Security Advisories and Notices
oCisco Threat Defense System
•Make sure all debugging commands in your router are turned off by issuing the undebug all or no
debug all commands. For more information on the use of debugging commands, refer to Using
Debug Commands.
•Are you able to issue show commands on the router? If yes, start collecting more information
immediately, using these showcommands.
•Is the router inaccessible? Can you reproduce this problem? If yes, power-cycle the router and,
before reproducing the problem, configure the scheduler interval 500 command. This scheduleslow priority processes to run every 500 milliseconds, which provides time for you to run some
commands, even if CPU usage is at 100 percent. On Cisco 7200 and Cisco 7500 Series Routers,
use the scheduler allocate 3000 1000 command.
•Does the router show symptoms of high CPU utilization at brief and unpredictable intervals? If
yes, periodically collect the output of the show processes cpu command, which shows if the high
CPU utilization is caused by interrupts or by a certain process. Use this UNIX script and, based on
the first findings, modify the script to collect data needed for further investigation of the issue.
From the following Link:
http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a00800a70f2.sh
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