350-401 Practice Test 21 — 15 Questions

Question 1

A network engineer issues the following command on Router R6:

R6# show ip nat translations
Pro Inside global      Inside local       Outside local      Outside global
--- 192.168.1.100      10.0.0.10          ---                ---
--- 192.168.1.101      10.0.0.11          ---                ---
udp 192.168.1.100:1234 10.0.0.10:1234     203.0.113.5:53     203.0.113.5:53
tcp 192.168.1.101:80   10.0.0.11:80       198.51.100.2:443   198.51.100.2:443

Based on this output, what is true about the NAT translations?

Accepted Answer

The translation for 10.0.0.10 to 192.168.1.100 is a dynamic NAT without PAT.. The output shows dynamic NAT translations with inside local and inside global addresses. The presence of protocol-specific translations (udp, tcp) indicates PAT (NAT overload) is in use for some traffic.

Answer

All translations are static NAT entries.

Answer

The router is performing only PAT (overload).

Answer

The outside global address is the same for all translations.

Question 2

A network engineer runs the following command on Router R1:

R1# show ip route 10.1.1.0
Routing entry for 10.1.1.0/24
  Known via "bgp 65001", distance 200, metric 0
  Tag 65002, type external
  Last update from 192.168.1.2 00:00:15 ago
  Routing Descriptor Blocks:
  * 192.168.1.2, from 192.168.1.2, 00:00:15 ago
      Route metric is 0, traffic share count is 1
      AS Hops 1
      Route tag 65002
      MPLS label: 18

Based on this output, what can be concluded?

Accepted Answer

The route is learned via BGP and has an MPLS label assigned, indicating MPLS forwarding.. The output shows a BGP route with an MPLS label, indicating that MPLS VPN or MPLS forwarding is in use. The presence of the MPLS label (18) in the routing table is the key clue.

Answer

The route is learned via OSPF and tagged with an MPLS label.

Answer

The route is a directly connected interface with an MPLS label.

Answer

The route is a static route with an MPLS label.

Question 3

A network engineer executes the following command on Router R5:

R5# show ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
10.0.0.6         1   FULL/DR         00:00:35    192.168.1.6    GigabitEthernet0/0
10.0.0.7         1   FULL/BDR        00:00:32    192.168.1.7    GigabitEthernet0/0
10.0.0.8         1   2WAY/DROTHER    00:00:38    192.168.1.8    GigabitEthernet0/0

Based on this output, what can be concluded about the OSPF network?

Accepted Answer

The OSPF network type is broadcast.. The output shows multiple OSPF neighbors on the same interface with different states: DR, BDR, and DROTHER. This indicates a broadcast multiaccess network (e.g., Ethernet) with OSPF DR/BDR election.

Answer

The OSPF network type is point-to-point.

Answer

Router R5 is the DR on this segment.

Answer

All neighbors are in the FULL state.

Question 4

A network engineer runs the following command on Router R9:

R9# show ip pim neighbor
PIM Neighbor Table
Neighbor Address     Interface          Uptime    Expires    Mode
192.168.1.10         GigabitEthernet0/0 1w2d      00:01:30   Dense
192.168.1.11         GigabitEthernet0/0 2w0d      00:01:25   Sparse
192.168.1.12         GigabitEthernet0/1 3d04h     00:01:28   Sparse

Based on this output, what can be concluded?

Accepted Answer

Router R9 has three PIM neighbors, one in Dense mode and two in Sparse mode.. The output shows PIM neighbors with different modes (Dense and Sparse). The mode indicates the PIM mode configured on the interface.

Answer

All PIM neighbors are operating in Sparse mode.

Answer

The PIM neighbor 192.168.1.12 is on the same interface as the others.

Answer

All PIM neighbors are in the 'Expires' state.

Question 5

A network engineer runs the following command on Router R4:

R4# show interfaces tunnel 0
Tunnel0 is up, line protocol is up
  Hardware is Tunnel
  Internet address is 10.0.0.4/30
  MTU 17916 bytes, BW 100 Kbit/sec, DLY 50000 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation TUNNEL, loopback not set
  Keepalive not set
  Tunnel source 192.168.1.4, destination 192.168.2.4
  Tunnel protocol/transport GRE/IP
    Key disabled, sequencing disabled
    Checksumming of packets disabled
  Last input never, output never, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/0 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     0 packets input, 0 bytes, 0 no buffer
     Received 0 broadcasts (0 IP multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     0 packets output, 0 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 unknown protocol drops
     0 output buffer failures, 0 output buffers swapped out

Based on this output, what is true about this tunnel?

Accepted Answer

The tunnel is a GRE tunnel that is up and operational.. The tunnel is up/up, uses GRE/IP encapsulation, and has a source and destination IP. The lack of traffic is indicated by zero packets input/output.

Answer

The tunnel is using IPsec encryption.

Answer

The tunnel is using MPLS over GRE.

Answer

The tunnel is down because there are no packets.

Question 6

A network engineer issues the following command on Router R8:

R8# show policy-map interface gigabitethernet 0/1
 GigabitEthernet0/1

Service-policy output: SHAPE-1M
    Class-map: class-default (match-any)
      0 packets, 0 bytes
      5 minute offered rate 0 bps, drop rate 0 bps
      Match: any
      queue limit 64 packets
      (queue depth 0)
      (congestion occurrences)
      shape (average) cir 1000000, bc 10000, be 10000
      target shape rate 1000000

Based on this output, what is true about the traffic shaping policy?

Accepted Answer

The policy is shaping traffic to an average rate of 1 Mbps.. The output shows a shaping policy applied in the output direction with a CIR of 1 Mbps. The class-default is used, meaning all traffic is shaped.

Answer

The policy is policing traffic to 1 Mbps.

Answer

The policy is dropping all traffic because the queue is full.

Answer

The policy is applied in the input direction.

Question 7

interface GigabitEthernet0/0
 ip address 192.168.1.1 255.255.255.0
 ip ospf network point-to-point
 ip ospf hello-interval 10
!
router ospf 1
 network 192.168.1.0 0.0.0.255 area 0

What is the effect of this configuration?

Accepted Answer

OSPF will use a 10-second hello interval and suppress DR/BDR election.. The configuration sets the OSPF network type to point-to-point and overrides the default hello interval (which for point-to-point is 10 seconds) to 10 seconds, which is actually the default for point-to-point. However, the key point is that the 'ip ospf network point-to-point' command changes the OSPF network type from broadcast to point-to-point, which disables DR/BDR election and uses a 10-second hello interval by default. The explicit hello-interval command is redundant but not harmful.

Answer

OSPF will use a 30-second hello interval and elect a DR/BDR.

Answer

OSPF will use a 10-second hello interval but still elect a DR/BDR.

Answer

OSPF will use a 30-second hello interval and suppress DR/BDR election.

Question 8

interface GigabitEthernet0/0
 ip address 10.0.0.1 255.255.255.252
 ip ospf network point-to-multipoint
 ip ospf hello-interval 30
!
router ospf 1
 network 10.0.0.0 0.0.0.3 area 0

What is the effect of this configuration?

Accepted Answer

OSPF will use a 30-second hello interval and form adjacencies with all neighbors without DR/BDR election.. The OSPF network type is set to point-to-multipoint, which is used for non-broadcast multi-access networks (like Frame Relay) but can also be used on Ethernet. The default hello interval for point-to-multipoint is 30 seconds, but here it is explicitly set to 30 seconds, which is the default. This network type does not elect DR/BDR and forms adjacencies with all neighbors.

Answer

OSPF will use a 10-second hello interval and elect a DR/BDR.

Answer

OSPF will use a 30-second hello interval and elect a DR/BDR.

Answer

OSPF will use a 10-second hello interval and form adjacencies with all neighbors without DR/BDR.

Question 9

What is the maximum hop count for EIGRP?

Accepted Answer

255. EIGRP uses a maximum hop count of 255 by default, though the default administrative distance is 90 for internal routes and 170 for external routes.

Answer

100

Answer

15

Answer

224

Question 10

Drag and drop the steps of IPsec IKEv2 tunnel establishment into the correct order, from first to last.

Accepted Answer

IKE_SA_INIT exchange (DH, nonces). IKEv2 establishment starts with IKE_SA_INIT to negotiate cryptographic parameters and exchange Diffie-Hellman keys. Next, IKE_AUTH authenticates the peers and establishes the first CHILD_SA. Then, additional CHILD_SAs can be created via CREATE_CHILD_SA. Finally, the IPsec SA is used to encrypt data traffic.

Question 11

interface Tunnel0
 ip address 10.0.0.1 255.255.255.252
 tunnel source GigabitEthernet0/0
 tunnel destination 203.0.113.2
 tunnel mode ipsec ipv4
!
crypto isakmp policy 10
 authentication pre-share
 encryption aes 256
 hash sha
 group 14
 lifetime 86400
!
crypto isakmp key cisco123 address 203.0.113.2
!
crypto ipsec transform-set TSET esp-aes 256 esp-sha-hmac
 mode tunnel
!
crypto map CMAP 10 ipsec-isakmp
 set peer 203.0.113.2
 set transform-set TSET
 match address 100
!
interface GigabitEthernet0/0
 crypto map CMAP
!
access-list 100 permit ip 10.0.0.0 0.0.0.3 10.0.0.4 0.0.0.3

What is the effect of this configuration?

Accepted Answer

The configuration creates an IPsec VTI that encrypts traffic between the two tunnel endpoints.. The configuration sets up a site-to-site IPsec VPN using a tunnel interface with IPsec protection. The crypto map is applied to the physical interface, and the access list defines interesting traffic between the two /30 subnets (10.0.0.0/30 and 10.0.0.4/30). This is a valid configuration for a DMVPN or static VTI, but note that the tunnel mode is 'ipsec ipv4' which is used for IPsec VTI (Virtual Tunnel Interface) and requires a crypto map on the physical interface to protect the tunnel. The access list correctly matches the tunnel networks.

Answer

The configuration will fail because the crypto map must be applied to the tunnel interface, not the physical interface.

Answer

The configuration will only encrypt traffic from 10.0.0.0/30 to 10.0.0.4/30, but not the reverse.

Answer

The configuration uses IKEv2 because of the transform-set and crypto map.

Question 12

interface GigabitEthernet0/0
 ip address 192.168.1.1 255.255.255.0
 ip ospf network non-broadcast
 ip ospf priority 1
!
router ospf 1
 network 192.168.1.0 0.0.0.255 area 0
 neighbor 192.168.1.2

What is the effect of this configuration?

Accepted Answer

OSPF will form an adjacency with 192.168.1.2 and elect a DR/BDR based on priority.. The OSPF network type is set to non-broadcast, which requires manual neighbor configuration. The 'neighbor' command is used to specify the neighbor IP. The priority is set to 1, which allows the router to participate in DR/BDR election. This is typical for Frame Relay or other NBMA networks.

Answer

OSPF will form an adjacency with 192.168.1.2 without DR/BDR election.

Answer

OSPF will automatically discover neighbors via multicast and form adjacencies.

Answer

OSPF will use a 30-second hello interval and suppress DR/BDR election.

Question 13

interface GigabitEthernet0/0
 ip address 192.168.1.1 255.255.255.0
 ip ospf network broadcast
 ip ospf priority 0
!
router ospf 1
 network 192.168.1.0 0.0.0.255 area 0

What is the effect of setting the OSPF priority to 0 on this interface?

Accepted Answer

The router will never become the DR or BDR on this segment.. Setting the OSPF priority to 0 on a broadcast network prevents the router from becoming the Designated Router (DR) or Backup Designated Router (BDR). It will never participate in the DR/BDR election and will only form full adjacencies with the DR and BDR.

Answer

The router will have a higher chance of becoming the DR.

Answer

The router will only form adjacencies with other routers that have priority 0.

Answer

The router will use a longer hello interval.

Question 14

What is the default OSPF hello interval on an Ethernet broadcast network?

Accepted Answer

10 seconds. On Ethernet broadcast networks, OSPF uses a default hello interval of 10 seconds.

Answer

30 seconds

Answer

40 seconds

Answer

20 seconds

Question 15

A network engineer is configuring a Cisco router as a DHCP relay agent to forward DHCP requests from a client VLAN to a centralized DHCP server located in a different subnet. The engineer configures the ip helper-address command on the VLAN interface. However, clients in the VLAN are not receiving IP addresses. The DHCP server is reachable from the router. What is the most likely cause?

Accepted Answer

The router does not have a return route to the client subnet, so the DHCP server's reply is dropped.. The ip helper-address command forwards DHCP broadcasts as unicasts to the specified server. If the DHCP server receives the request but the reply cannot be routed back to the client, the client will not get an address. This often happens when the router does not have a route back to the client subnet.

Answer

The ip helper-address command is applied on the wrong interface (e.g., the interface facing the DHCP server).

Answer

The DHCP server is not configured with a scope for the client subnet.

Answer

The DHCP client is using DHCPv6 instead of DHCPv4.