300-410 Practice Test 6 — 10 Questions

Question 1

A network engineer runs the following command to verify BFD session details:

NeighAddr      LD/RD         RH/RS     State     Int
10.4.4.2      100/200       Up        Up        Gi0/1
MinTxInt: 500000, MinRxInt: 500000, Multiplier: 5

What does this output indicate?

Accepted Answer

BFD session is UP with a detection time of 2.5 seconds (500 ms * 5).. The output shows a BFD session with a multiplier of 5 and intervals of 500 ms. The high multiplier may indicate a need for more tolerance, but the session is UP.

Answer

BFD session is DOWN due to high multiplier.

Answer

BFD is using echo mode for faster detection.

Answer

BFD multiplier is set to 3, not 5.

Question 2

Which TWO statements correctly describe the behavior of the 'default-information originate' command in the context of route redistribution? (Choose TWO.)

Accepted Answer

In OSPF, the 'default-information originate' command always injects a default route into the OSPF domain, even if no default route exists in the routing table, provided the 'always' keyword is used.. The 'default-information originate' command in OSPF and EIGRP has specific behaviors. In OSPF, it always originates a default route regardless of the routing table, unless the 'always' keyword is omitted and there is no default route in the routing table. In EIGRP, it requires a default route in the routing table to inject the default, unless the 'always' keyword is used. The command does not automatically redistribute all routes; it only injects a default route.

Answer

In EIGRP, the 'redistribute static' command automatically injects a default route if a static default route is configured.

Answer

In OSPF, the 'default-information originate always' command will inject a default route even if OSPF is not configured on any interface.

Answer

In both OSPF and EIGRP, the 'default-information originate' command automatically redistributes all connected routes into the routing protocol.

Question 3

Which TWO statements about IPv6 Neighbor Discovery (ND) Inspection are true? (Choose TWO.)

Accepted Answer

It validates Neighbor Solicitation and Neighbor Advertisement messages against the IPv6 snooping binding table.. IPv6 ND Inspection validates Neighbor Solicitation (NS) and Neighbor Advertisement (NA) messages against the IPv6 snooping binding table. This table is built by gleaning information from DHCPv6 messages or by using the IPv6 Neighbor Discovery protocol itself, ensuring that only legitimate ND messages from trusted sources are forwarded, preventing attacks like Neighbor Cache exhaustion or address spoofing.

Answer

It prevents rogue DHCPv6 servers from assigning malicious addresses.

Answer

It uses a prefix list to determine which source addresses are allowed.

Answer

It is enabled globally and cannot be applied on a per-interface basis.

Question 4

Drag and drop the steps to verify and validate DHCP (IPv4 and IPv6) operational state into the correct order, from first to last.

Accepted Answer

Display DHCP pool statistics and bindings. Start by checking the DHCP pool utilization and bindings. Then, verify that clients have received addresses from the correct pool. Next, confirm that the DHCP relay agent is forwarding packets. After that, validate DHCPv6 prefix delegation if used. Finally, ensure that the DHCP server is not running out of addresses.

Question 5

An engineer configures a DHCP server on a Cisco router to assign IP addresses from a pool. Clients receive addresses, but when the engineer checks 'show ip dhcp binding', no bindings are displayed. Which is the most likely explanation?

Accepted Answer

The 'ip dhcp excluded-address' command includes the entire pool range, so no addresses are assigned and no bindings are created.. The 'show ip dhcp binding' command only displays bindings that are currently active. If the lease time is very short or the clients release addresses, bindings may not appear. However, a more subtle edge case is when the DHCP server is configured with 'ip dhcp excluded-address' that includes the pool range, causing the server to not assign addresses but still respond with NAKs.

Answer

The DHCP pool is configured with 'lease infinite', causing bindings to be stored in a different database.

Answer

The router's DHCP server is configured in 'database' mode, which stores bindings externally.

Answer

The clients are using DHCPv6, not DHCPv4.

Question 6

Which of the following is NOT a valid match criterion for a class-map used in Control Plane Policing?

Accepted Answer

match protocol. In Control Plane Policing (CoPP), class-maps are used to classify traffic destined to the control plane. The valid match criteria include match access-group, match ip dscp, and match ip precedence. However, match protocol is not a valid match criterion for a class-map under CoPP; it is used in other contexts like QoS policy-maps for application-level classification, but not for CoPP class-maps.

Answer

match access-group

Answer

match ip dscp

Answer

match ip precedence

Question 7

A network engineer runs the following command on Router R1:

R1# show ip ospf neighbor detail

Neighbor 10.1.1.4, interface address 192.168.14.4
    In the area 0 via interface GigabitEthernet0/2
    Neighbor priority is 1, State is 2WAY, 2 state changes
    DR is 10.1.1.1, BDR is 10.1.1.4
    Options is 0x12 (L L S R)
    Dead timer due in 00:00:38
    Neighbor is up for 00:05:22
    Index 1/1/1, retransmission queue length 0, number of retransmission 0
    First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0)
    Last retransmission scan length is 0, time is 0 msec
    Last retransmission scan time is 0 msec

Based on this output, what is the problem?

Accepted Answer

The neighbor is in 2WAY state, meaning the adjacency is not fully established.. The neighbor state is 2WAY, not FULL. This indicates that the neighbor relationship has not progressed to full adjacency. On a broadcast network, routers in 2WAY state have exchanged hello packets but have not completed database exchange. This could be due to mismatched MTU, authentication, or other issues, but the key observation is that the state is not FULL.

Answer

Router R1 is the DR and the neighbor is the BDR, so the state is correct.

Answer

The dead timer is about to expire, causing the neighbor to go down.

Answer

The neighbor has a lower priority than R1, so it remains in 2WAY.

Question 8

A network engineer runs the following command to troubleshoot an MPLS L3VPN issue:

R1# show bgp vpnv4 vrf CUSTOMER-A 10.1.1.0/24

Output:
BGP routing table entry for 10.1.1.0/24, version 10
Paths: (1 available, best #1, table CUSTOMER-A)
  Advertised to update-groups:
     1
  Refresh Epoch 1
  Local
    0.0.0.0 from 0.0.0.0 (10.0.0.1)
      Origin incomplete, metric 0, localpref 100, weight 32768, valid, sourced, best
      Extended Community: RT:100:100
      mpls labels in/out nolabel/nolabel

What does this output indicate?

Accepted Answer

The route is locally originated and has no MPLS label. This shows a VPNv4 route for prefix 10.1.1.0/24 in VRF CUSTOMER-A. The path is local (sourced from this router), with next hop 0.0.0.0, and the route is valid and best. The extended community is RT:100:100. The mpls labels show nolabel/nolabel, meaning no MPLS label is assigned for this prefix, which could indicate a problem if labels are expected.

Answer

The route is learned from a BGP peer

Answer

The route has an MPLS label of 100

Answer

The route is not best

Question 9

An engineer configures CoPP on a router running EIGRP. The policy includes a class-map matching EIGRP traffic with a police rate of 1000 pps. After applying the policy, EIGRP neighbors form but occasionally go active and become stuck-in-active (SIA). Which is the most likely explanation?

Accepted Answer

The police rate in pps is too low, causing EIGRP reliable packets (queries/replies) to be dropped, leading to SIA.. EIGRP uses RTP (Reliable Transport Protocol) for certain packets like queries and replies. These reliable packets require acknowledgment; if the CoPP police rate of 1000 pps is too low, EIGRP queries or replies may be dropped. Missing acknowledgments cause the neighbor to be declared active, and if the query process is not completed within the active timer, the route becomes stuck-in-active (SIA).

Answer

EIGRP uses multicast, and CoPP cannot police multicast traffic.

Answer

CoPP only affects incoming traffic, but EIGRP SIA is caused by outgoing packet drops.

Answer

EIGRP uses TCP, and CoPP only polices UDP.

Question 10

Which THREE statements about NAT and PAT behavior in Cisco IOS are true? (Choose THREE.)

Accepted Answer

PAT allows multiple inside hosts to share a single public IP address by using unique source port numbers.. PAT (Port Address Translation) extends NAT by using unique source port numbers to multiplex multiple inside hosts over a single public IP address. This allows many internal devices to share one external IP, with the router tracking each session by the combination of inside global IP and port.

Answer

The 'ip nat inside source static' command automatically enables PAT when multiple inside hosts are configured.

Answer

The 'ip nat pool' command is required for all PAT configurations.