300-410 Practice Test 36 — 15 Questions

Question 1

A network engineer runs the following command on Router R1:

R1# show ip eigrp topology
EIGRP-IPv4 Topology Table for AS(100)/ID(192.168.1.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
       r - reply Status, s - sia Status

P 10.10.10.0/24, 1 successors, FD is 28160
         via 10.1.1.2 (28160/28160), GigabitEthernet0/0
P 10.20.20.0/24, 1 successors, FD is 28160
         via 10.2.2.2 (28160/28160), GigabitEthernet0/1
P 10.30.30.0/24, 1 successors, FD is 28160
         via 10.3.3.2 (28160/28160), GigabitEthernet0/2
A 10.40.40.0/24, 0 successors, FD is Infinity
         via 10.4.4.2 (Infinity/Infinity), GigabitEthernet0/3

Based on this output, what is the problem?

Accepted Answer

The route to 10.40.40.0/24 is stuck-in-active and may cause a network instability.. The topology table shows that the route to 10.40.40.0/24 is in Active state (A), meaning the router is actively querying for a successor. The FD is Infinity, indicating no feasible successor is available. This could be due to a network failure or a stuck-in-active condition.

Answer

The route to 10.40.40.0/24 is passive and stable.

Answer

The route to 10.30.30.0/24 has a feasible successor.

Answer

All routes are in a stable passive state.

Question 2

Which TWO statements correctly describe the use of SNMP inform requests compared to traps? (Choose TWO.)

Accepted Answer

Informs require the NMS to send an acknowledgment back to the router.. Informs are confirmed notifications; the NMS sends an acknowledgment, and the router retransmits if no ack is received. Traps are unconfirmed. Informs consume more resources (memory, CPU) due to retransmission handling. Both can be enabled with 'snmp-server enable traps' and directed with 'snmp-server host' using the 'informs' keyword. The default retransmission timeout for informs is 30 seconds. Informs are more reliable than traps.

Answer

Traps are more reliable than informs because they use UDP with a higher priority.

Answer

Informs and traps are mutually exclusive; a router can only send one type to a given NMS.

Question 3

A network engineer runs the following command on Router R1:

R1# show ip eigrp interfaces
EIGRP-IPv4 Interfaces for AS(100)
                       Xmit Queue   Mean   Pacing Time   Multicast    Pending
Interface        Peers  Un/Reliable  SRTT   Un/Reliable   Flow Timer   Routes
Gi0/0              1       0/0       12       0/10         50           0
Gi0/1              1       0/0       15       0/10         50           0
Gi0/2              1       0/0       18       0/10         50           0
Gi0/3              1       0/0       20       0/10         50           0
Gi0/4              0       0/0        0       0/10         50           0

Based on this output, which statement is correct?

Accepted Answer

Interface Gi0/4 has no EIGRP neighbor, which may indicate a configuration issue or lack of connectivity.. The show ip eigrp interfaces command shows EIGRP-enabled interfaces and their statistics. Gi0/4 has 0 peers, meaning no EIGRP neighbor is formed on that interface. The other interfaces have 1 peer each, indicating a neighbor relationship.

Answer

All interfaces have at least one EIGRP neighbor.

Answer

The mean SRTT on Gi0/2 is 18 ms, which is too high and indicates a problem.

Answer

The pending routes count of 0 on all interfaces indicates a routing loop.

Question 4

Consider the following EIGRP configuration on Router R4:

router eigrp 300
 variance 2
 network 172.16.0.0

What is the purpose of the variance command?

Accepted Answer

It allows load balancing over paths with metrics up to twice the best metric.. The variance command allows EIGRP to load-balance across multiple paths whose metric is within the variance multiplier times the best metric. A variance of 2 means paths with a metric up to twice the best metric can be used for load balancing.

Answer

It sets the maximum number of equal-cost paths to 2.

Answer

It sets the EIGRP metric weight for delay to 2.

Question 5

Which TWO configuration steps are required to enable EIGRP authentication between two directly connected routers? (Choose TWO.)

Accepted Answer

Configure a key chain with a key string on both routers.. EIGRP authentication requires a key chain with a key string and the authentication mode set to md5 (or hmac-sha-256) on the interface. The key chain must be defined globally, and then the interface configuration references it. The other options are incorrect because authentication is per-interface, not per-process, and the key chain name must match on both sides.

Answer

Apply the authentication mode and key chain under the EIGRP router process.

Answer

Set the same autonomous system number in the key chain configuration.

Answer

Ensure the key chain name is different on each router to prevent conflicts.

Question 6

A network engineer runs the following command on Router R1:

R1# show ip eigrp traffic
EIGRP-IPv4 Traffic Statistics for AS(100)
  Hellos sent/received: 5000/4995
  Updates sent/received: 150/148
  Queries sent/received: 10/8
  Replies sent/received: 8/10
  Acks sent/received: 300/298
  Input queue high water mark: 10
  Input queue drops: 0
  SIA-Queries sent/received: 0/0
  SIA-Replies sent/received: 0/0
  Hello process ID: 123
  PDM process ID: 124
  Socket queue: 0/2000/10/0 (current/max/highest/drops)
  Input queue: 0/2000/10/0 (current/max/highest/drops)

Based on this output, which statement is correct?

Accepted Answer

The EIGRP process is operating normally with no signs of issues.. The EIGRP traffic statistics show a balanced number of sent and received packets. There are no input queue drops, no SIA-Queries or SIA-Replies, indicating a healthy EIGRP process. The ratio of queries to replies is nearly balanced (10 sent vs 8 received, 8 sent vs 10 received), which is normal.

Answer

There is a problem because more queries were sent than replies received.

Answer

The input queue drops of 0 indicate that the router is not processing EIGRP packets.

Answer

The SIA-Queries count of 0 indicates that the network has experienced stuck-in-active events.

Question 7

A network engineer runs the following command on Router R1:

R1# show ip eigrp topology 10.50.50.0/24
EIGRP-IPv4 Topology Entry for AS(100)/ID(192.168.1.1) for 10.50.50.0/24
  State: Active, Reply status: 0, Originating router: 192.168.1.1
  Routing Descriptor Blocks:
  10.1.1.2 (GigabitEthernet0/0), from 10.1.1.2, Send flag: 0x0
      Composite metric: (4294967295/4294967295), Route is Internal
      Vector metric:
        Minimum bandwidth: 100000 Kbit
        Total delay: 100 microseconds
        Reliability: 255/255
        Load: 1/255
        Minimum MTU: 1500
        Hop count: 1

Based on this output, what is the problem?

Accepted Answer

The route is in Active state with an infinite metric, indicating that the router has lost the route and is querying for a new path.. The route to 10.50.50.0/24 is in Active state, meaning the router is actively querying for a successor. The composite metric is 4294967295 (Infinity), indicating that the route is unreachable. This is a problem because the router has lost the route and is trying to find an alternative path.

Answer

The route is passive and stable.

Answer

The metric of 4294967295 is normal for a summary route.

Answer

The hop count of 1 indicates the route is one hop away and reachable.

Question 8

A network engineer runs the following command on Router R1:

R1# show ip eigrp neighbors detail
EIGRP-IPv4 Neighbors for AS(100)
H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                           (sec)         (ms)       Cnt Num
0   10.1.1.2                Gi0/0            13 00:12:34   12   200  0  45
   Version 12.0/2.0, Retrans: 0, Retries: 0, Restarts: 0
   Topology ids from peer: 0
   Passive interface: No
   Hello interval: 5
   Hold time: 15

Based on this output, what is the problem?

Accepted Answer

The neighbor is operating normally with no issues.. The detail output shows the neighbor is up with normal parameters. However, the 'Passive interface: No' indicates that the interface is not configured as passive, which is expected for forming neighbors. There is no problem evident; the neighbor is functioning correctly.

Answer

The interface is configured as passive, preventing neighbor formation.

Answer

The neighbor has a high number of retransmissions.

Answer

The hold time of 15 seconds is too short and may cause flapping.

Question 9

A network engineer runs the following command on Router R1:

R1# show ip eigrp topology 10.10.10.0/24
EIGRP-IPv4 Topology Entry for AS(100)/ID(192.168.1.1) for 10.10.10.0/24
  State: Passive, Reply status: 0, Originating router: 192.168.1.1
  Routing Descriptor Blocks:
  0.0.0.0 (Null0) from 0.0.0.0, Send flag: 0x0
      Composite metric: (2560000000/0), Route is Internal
      Vector metric:
        Minimum bandwidth: 100000 Kbit
        Total delay: 100 microseconds
        Reliability: 255/255
        Load: 1/255
        Minimum MTU: 1500
        Hop count: 0

Based on this output, what is the problem?

Accepted Answer

The route is a local summary route pointing to Null0, which is normal for EIGRP summarization.. The route to 10.10.10.0/24 is a local summary or null0 route (via Null0). This is typical for a summary route or a route to a directly connected network. The composite metric of 2560000000/0 indicates a very high metric, which is normal for a null0 route. There is no problem; this is a common configuration.

Answer

The route has a metric of 2560000000, indicating a network failure.

Answer

The hop count of 0 means the route is not reachable.

Answer

The route is in Active state, indicating a problem.

Question 10

What is the default administrative distance for internal EIGRP routes?

Accepted Answer

90. Cisco IOS assigns an administrative distance of 90 to internal EIGRP routes. External EIGRP routes have a distance of 170.

Answer

110

Answer

120

Answer

170

Question 11

A network engineer configures SNMPv3 on a router with the 'snmp-server group' and 'snmp-server user' commands, using SHA for authentication and AES for privacy. The NMS can poll the router successfully, but SNMP traps are not received. Which is the most likely explanation?

Accepted Answer

The SNMP engine ID on the router changed after the NMS was configured, causing authentication failures for traps.. SNMPv3 traps require that the engine ID be known to both the agent and the NMS. If the engine ID changes (e.g., due to a reload or configuration change), the NMS may not recognize the trap sender, causing traps to be dropped. Additionally, traps use a different notification view than the read view used for polling.

Answer

The 'snmp-server enable traps' command was omitted, so no traps are generated.

Answer

The NMS is using SNMPv2c for trap reception, which is incompatible with SNMPv3.

Answer

The 'snmp-server host' command specifies a community string instead of the SNMPv3 username.

Question 12

A network engineer runs the following command on Router R1:

R1# show ip eigrp interfaces detail Gi0/0
EIGRP-IPv4 Interfaces for AS(100)
Interface: GigabitEthernet0/0
  Peers: 1
  Xmit Queue Un/Reliable: 0/0
  Mean SRTT: 12
  Pacing Time Un/Reliable: 0/10
  Multicast Flow Timer: 50
  Pending Routes: 0
  Hello interval: 5
  Hold time: 15
  Split horizon: Enabled
  Next multicast: 0.0.0.0
  Next broadcast: 0.0.0.0

Based on this output, what is the problem?

Accepted Answer

Split horizon is enabled, which is a normal and expected configuration.. The detail output shows split horizon is enabled on the interface. Split horizon is a loop prevention mechanism that prevents routes from being advertised out the interface they were learned on. This is normal and expected. There is no problem.

Answer

Split horizon is disabled, which could cause routing loops.

Answer

The hold time of 15 seconds is too short and may cause instability.

Answer

The interface has no peers, indicating a problem.

Question 13

Given the following configuration snippet on Router R5:

router eigrp 400
 network 10.1.1.0 0.0.0.255

What is wrong with this configuration?

Accepted Answer

The configuration is correct as shown.. The network command in EIGRP uses a wildcard mask, but the mask 0.0.0.255 is correct for a /24 prefix. However, the network address 10.1.1.0 is a subnet, which is valid. There is no error; the configuration is correct.

Answer

The wildcard mask should be 255.255.255.0.

Answer

The network address should be the classful network 10.0.0.0.

Answer

The AS number 400 is invalid; EIGRP AS numbers must be between 1 and 65535.

Question 14

Which THREE symptoms indicate that EIGRP is experiencing a neighbor relationship issue due to an MTU mismatch? (Choose THREE.)

Accepted Answer

The neighbor adjacency repeatedly goes up and down.. An MTU mismatch causes EIGRP packets to be fragmented or dropped, leading to repeated retransmissions and neighbor flapping. The 'show ip eigrp neighbors' output shows increasing retransmission counts and possibly a stuck-in-active (SIA) state. The neighbor may repeatedly go up and down. Option C is false because the 'show ip eigrp topology' shows routes, not neighbor state. Option E is false because the hold time is a timer, not a direct symptom of MTU issues.

Answer

The 'show ip eigrp topology' command shows routes in active state.

Answer

The 'show ip eigrp interfaces' command shows a hold time of zero.

Question 15

Consider the following EIGRP configuration on Router R1:

router eigrp 100
 network 10.0.0.0
 passive-interface default
 no passive-interface GigabitEthernet0/0

What is the effect of this configuration?

Accepted Answer

EIGRP will form neighbor adjacencies only on GigabitEthernet0/0.. The configuration sets all interfaces to passive by default, then re-enables EIGRP on GigabitEthernet0/0. This means only GigabitEthernet0/0 will send and receive EIGRP hello packets and form adjacencies; all other interfaces will only advertise networks without forming neighbors.

Answer

EIGRP will form neighbor adjacencies on all interfaces.

Answer

EIGRP will not form any neighbor adjacencies.

Answer

EIGRP will form neighbor adjacencies on all interfaces except GigabitEthernet0/0.