4.1 Diagnose Network Problems Using Such as Debugs, Conditional Debugs, Traceroute, Ping, SNMP, and Syslog 350-401 Practice Questions (Page 3)

Questions 11–15

1. 11foundation · easy

   What is the primary purpose of syslog messages in network troubleshooting?

   • ATo automatically reconfigure the device to prevent failures
   • BTo actively test connectivity between devices
   • CTo replace the need for debug commands entirely
   • DTo provide a chronological record of events and errors that can be correlated to diagnose issues
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2. 12expert · hard

   A network engineer is troubleshooting intermittent BGP session drops between two routers. The drops occur randomly, sometimes several times a day, and the engineer needs to capture the exact reason for the drops. The engineer has access to both routers and can schedule maintenance windows, but the drops are unpredictable. Which approach would provide the most reliable diagnostic data without requiring constant manual monitoring?

   • AUse SNMP to poll BGP peer state every minute and review the data later.
   • BSchedule a maintenance window and enable 'debug ip bgp' without any filters, then manually monitor the output.
   • CRun a continuous ping from a monitoring station to the remote router's IP address.
   • DEnable 'debug ip bgp' with conditional debugging on the neighbor and log the output to a syslog server.
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4. 13application · medium

   A network engineer is troubleshooting a recurring OSPF neighbor flap. The engineer needs to correlate the exact time of the flap with other network events. The router's clock is not synchronized with the syslog server. What should the engineer do first to improve the accuracy of the correlation?

   • AConfigure NTP on the router to synchronize its clock with the syslog server.
   • BEnable 'debug ip ospf events' to capture detailed neighbor state changes.
   • CIncrease the syslog severity level to 'informational' on the router.
   • DUse the 'show logging' command to review the router's local logs.
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5. 14application · medium

   A network operations team is investigating a recurring issue where a core switch's CPU utilization spikes every night at the same time. They want to identify the cause without manually logging into the device every night. Which approach would provide the most useful diagnostic data?

   • ASet up syslog to capture all messages and review them the next morning.
   • BEnable 'debug ip cpu' on the switch and leave it running overnight.
   • CConfigure SNMP to poll the switch's CPU utilization every minute and store the data on a monitoring server.
   • DRun a continuous ping to the switch from the monitoring server overnight.
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6. 15expert · hard

   A network engineer is troubleshooting a problem where OSPF adjacencies are flapping on a core router. The engineer has enabled 'debug ip ospf adjacency' and sees that the adjacencies are going down due to 'Dead timer expired'. The engineer wants to determine if the issue is caused by high CPU utilization on the router or by a network problem. Which additional diagnostic step would be most useful?

   • ACheck the router's CPU utilization using SNMP or 'show process cpu'.
   • BEnable 'debug ip ospf hello' to see if hello packets are being sent.
   • CRun a traceroute to the neighbor router to check the path.
   • DCheck the syslog for OSPF events.
   Reveal Solution Discussion Select an answer first