300-410 Device Management — Timed 10 Questions

Question 1

A network engineer is troubleshooting a router that is not sending SNMP traps to the NMS server at 10.1.1.100. The SNMP configuration includes 'snmp-server enable traps' and 'snmp-server host 10.1.1.100 version 2c public'. The engineer can ping the NMS server from the router, and 'show snmp' indicates SNMP is enabled. What is the most likely cause of the missing traps?

Accepted Answer

The 'snmp-server trap-source' command is missing, causing traps to use an incorrect source IP.. The router has SNMP traps enabled and a host configured, but the 'snmp-server trap-source' command is missing, causing traps to be sourced from an interface that may not be reachable or may have an incorrect source IP that the NMS expects.

Answer

The NMS server is not listening on UDP port 162.

Answer

The SNMP community string 'public' is not configured on the router.

Answer

The router's ACL is blocking outbound UDP traffic to port 162.

Question 2

An engineer is troubleshooting a router that fails to write its running configuration to startup configuration using 'copy running-config startup-config'. The command returns 'Destination filename [startup-config]?' and then the prompt returns without error. 'show startup-config' shows an empty configuration. What is the most likely cause?

Accepted Answer

The router is configured to boot from a TFTP server using the 'boot host' command, and the TFTP server is unreachable or does not allow writes.. The router may have insufficient space in NVRAM or the startup configuration file may be corrupted. However, a common issue is that the router is booting from a network server (TFTP) and the 'boot host' command points to a remote file, so 'copy running-config startup-config' attempts to write to the remote server but fails silently.

Answer

The NVRAM is full and the router cannot save the configuration.

Answer

The 'file prompt quiet' command is configured, suppressing prompts.

Answer

The router is running in ROMMON mode.

Question 3

A network engineer is troubleshooting a router that has been running for 200 days. The router experiences a sudden reboot, and after reload, the configuration is missing. 'show startup-config' returns 'startup-config is not present'. The engineer checks the boot variable: 'boot system flash:ios-image.bin'. What is the most likely cause of the configuration loss?

Accepted Answer

The engineer did not execute 'copy running-config startup-config' before the reboot.. The router likely has a corrupt NVRAM or the startup configuration was never saved. However, the key clue is that the router has been running for 200 days without a save, and the 'copy running-config startup-config' was not performed, so the startup-config is empty or missing.

Answer

The router's NVRAM has a hardware failure and lost the configuration.

Answer

The 'boot system' command points to a TFTP server that also contains a configuration file, overwriting the local startup-config.

Answer

The router's configuration register is set to 0x2142, ignoring startup-config.

Question 4

An engineer is troubleshooting a router that is not sending syslog messages to the syslog server at 192.168.1.10. The configuration includes 'logging host 192.168.1.10' and 'logging trap informational'. The engineer can ping the syslog server from the router. 'show logging' shows that the logging buffer is filling with messages. What is the most likely cause?

Accepted Answer

The 'logging source-interface' command is missing, causing syslog messages to use an incorrect source IP.. The router has logging to a remote host configured, but the 'logging source-interface' is missing, so syslog messages are sourced from the outgoing interface IP, which may not be reachable or may be filtered by the server.

Answer

The syslog server is not listening on UDP port 514.

Answer

The 'logging on' command is not configured.

Answer

The syslog server's IP address is incorrect in the configuration.

Question 5

A network engineer is troubleshooting a router that is not responding to ICMP echo requests from a management station at 10.10.10.1. The router has an ACL applied to the VTY lines that permits only 10.10.10.0/24. The engineer can telnet to the router from the management station. What is the most likely cause?

Accepted Answer

An inbound ACL on the interface denies ICMP from 10.10.10.1.. Telnet is permitted by the VTY ACL, but ICMP is controlled by an interface ACL or the global 'ip icmp rate-limit' feature. The most likely cause is an inbound ACL on the interface that denies ICMP from the management station.

Answer

The VTY ACL also applies to ICMP traffic.

Answer

The router has 'no ip icmp echo' configured globally.

Answer

The management station is not in the routing table of the router.

Question 6

An engineer is troubleshooting a router that is configured as an NTP client. The router's clock is not synchronizing with the NTP server at 192.168.1.1. 'show ntp status' shows 'clock is unsynchronized', and 'show ntp associations' shows the server as '.INIT.' with no reachability. The engineer can ping the NTP server. What is the most likely cause?

Accepted Answer

The NTP server is not configured to respond to NTP requests from this client.. The NTP server may be reachable via ping, but NTP uses UDP port 123. The router may have an ACL blocking NTP traffic, or the NTP server may not be responding. However, a common issue is that the NTP server is not configured to serve time to the client, or the client's NTP source interface is incorrect.

Answer

The router's 'ntp source' command is missing, causing NTP packets to use an incorrect source IP.

Answer

The router's clock is set too far in the future, causing NTP to reject the server's time.

Answer

The router has 'ntp authenticate' enabled without the proper key.

Question 7

A network engineer is troubleshooting a router that is not responding to SNMP polls from the NMS at 10.1.1.100. The SNMP configuration includes 'snmp-server community public RO' and 'snmp-server community private RW'. The engineer can ping the router from the NMS. 'show snmp' shows SNMP is enabled. What is the most likely cause?

Accepted Answer

An ACL is applied to the SNMP community that denies the NMS IP.. The router has SNMP communities configured, but an ACL may be applied to the community that restricts access. The most common issue is an access-list applied to the community string that does not permit the NMS IP.

Answer

The NMS is using the wrong SNMP version.

Answer

The router's SNMP agent is disabled due to high CPU.

Answer

The NMS is using the wrong community string.

Question 8

An engineer is troubleshooting a router that is configured to archive configurations to a TFTP server at 192.168.1.10. The 'archive' configuration includes 'path tftp://192.168.1.10/config-archive' and 'write-memory'. The engineer notices that the archive is not being created after 'copy running-config startup-config'. What is the most likely cause?

Accepted Answer

The TFTP server does not have write permissions for the directory.. The archive 'write-memory' command triggers an archive when the startup-config is written, but the TFTP server may not allow file creation, or the path is incorrect. A common issue is that the TFTP server requires a filename, not a directory path, or the server is not reachable.

Answer

The 'archive' configuration is missing the 'time-period' command.

Answer

The router's 'file prompt quiet' command is configured, suppressing error messages.

Answer

The TFTP server's IP address is incorrect in the path.

Question 9

A network engineer is troubleshooting a router that is not allowing SSH connections from any management station. The router has 'ip domain-name example.com' and 'crypto key generate rsa' configured. 'line vty 0 4' has 'transport input ssh' and 'login local'. The engineer can ping the router from a management station. What is the most likely cause?

Accepted Answer

The RSA key was generated with a modulus less than 768 bits, causing SSH to fail.. SSH requires proper AAA or local authentication, and the VTY lines must have 'login local' or AAA configured. However, a common issue is that the RSA key is not generated with sufficient modulus size (minimum 768 bits for SSHv2).

Answer

The VTY lines are missing the 'login local' command.

Answer

The router has 'ip ssh version 1' configured, and the client only supports SSHv2.

Answer

The management station is using the wrong username or password.

Question 10

A network engineer runs the following command on Router R1:

R1# show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                           (sec)         (ms)       Cnt Num
0   192.168.1.2             Gi0/0            13 00:12:34   10   200  0  15
1   192.168.2.2             Gi0/1            10 00:10:22   12   200  0  22
2   10.10.10.2              Gi0/2            14 00:08:15   15   200  0  18

Based on this output, which statement is correct?

Accepted Answer

All EIGRP neighbors are operating normally.. The output shows three EIGRP neighbors with normal hold timers and uptimes. The Q count is 0 for all, indicating no queued packets. The SRTT and RTO values are low, indicating good network conditions. There is no problem evident in this output.

Answer

Neighbor 192.168.1.2 has a high SRTT indicating a slow link.

Answer

Neighbor 10.10.10.2 is experiencing packet loss due to high RTO.

Answer

The Q count of 0 indicates that EIGRP is not exchanging routes.