300-410 Practice Exam 63 — 20 Questions

Question 1

Which BGP message type is used to advertise, withdraw, and update routes?

Accepted Answer

UPDATE. BGP UPDATE messages carry path attributes and NLRI for route advertisements and withdrawals.

Answer

OPEN

Answer

NOTIFICATION

Answer

KEEPALIVE

Question 2

A network engineer runs the following command on Router R1:

R1# show ip policy
Interface     Route-map
GigabitEthernet0/0      PBR-QOS

R1# show route-map PBR-QOS
route-map PBR-QOS, permit, sequence 10
  Match clauses:
    ip address (access-lists): 120
  Set clauses:
    ip next-hop 10.0.0.2
  Policy routing matches: 500 packets, 45000 bytes

R1# show access-lists 120
Extended IP access list 120
    10 permit ip 192.168.1.0 0.0.0.255 any

R1# debug ip policy
Policy routing debugging is on
*Mar  1 00:05:23.123: IP: s=192.168.1.100 (GigabitEthernet0/0), d=8.8.8.8, len 100, policy match
*Mar  1 00:05:23.123: IP: s=192.168.1.100 (GigabitEthernet0/0), d=8.8.8.8, len 100, policy rejected

Based on this output, what is the most likely problem?

Accepted Answer

The next-hop 10.0.0.2 is unreachable.. The debug output shows 'policy match' followed by 'policy rejected'. This indicates that the packet matched the route map, but the set clause was not applied because the next-hop is unreachable or the route map's set condition fails (e.g., verify-availability if used, or next-hop not in routing table). The show route-map shows matches, but the packet is rejected and forwarded normally.

Answer

The access list 120 is misconfigured.

Answer

The route map is applied to the wrong interface.

Answer

The route map sequence number is incorrect.

Question 3

Examine the following OSPF configuration on router R1:

router ospf 1
 network 10.0.0.0 0.255.255.255 area 0
 network 192.168.1.0 0.0.0.255 area 1

What is the effect of this configuration?

Accepted Answer

All interfaces with IP addresses in the 10.0.0.0/8 range will be enabled for OSPF in area 0, and interfaces in 192.168.1.0/24 will be in area 1.. The network statements define which interfaces participate in OSPF and assign them to areas. The first statement covers all interfaces with IP addresses starting with 10.x.x.x, and the second covers 192.168.1.x. This is a valid configuration.

Answer

Only the interface with IP 10.0.0.1 will be in area 0; all other 10.x.x.x interfaces are ignored.

Answer

The configuration is invalid because OSPF process 1 cannot have two network statements in different areas.

Answer

The configuration will cause a routing loop between area 0 and area 1.

Question 4

What is the default OSPF hello interval on a Cisco IOS-XE router for a broadcast network type?

Accepted Answer

10 seconds. The default hello interval for OSPF on broadcast and point-to-point networks is 10 seconds, as defined by RFC 2328 and implemented in Cisco IOS-XE.

Answer

30 seconds

Answer

40 seconds

Answer

60 seconds

Question 5

An EIGRP network is experiencing stuck-in-active (SIA) routes after a link failure. Router R1 has the following relevant configuration: router eigrp 100 network 10.0.0.0 0.255.255.255 Router R2 shows: show ip eigrp topology 10.1.1.0/24 IP-EIGRP topology entry for 10.1.1.0/24 State: Active, 00:01:30, Reply status 10.2.2.2, 10.3.3.3 What is the root cause?

Accepted Answer

Query scope is too wide; configure stub routing or summarization to limit queries.. The route is stuck-in-active because queries are sent to all neighbors and one or more are not replying. This can be due to query scope issue where routers in the query path have no route and keep querying further, causing timeout. The correct fix is to use summary routes or distribute-lists to limit query scope.

Answer

The K-values are mismatched; check metric weights.

Answer

The network command includes too many interfaces; use passive-interface.

Answer

The hold time is too short; increase to 180 seconds.

Question 6

Which TWO actions will prevent a CoPP policy from inadvertently dropping legitimate routing protocol packets during a traffic spike? (Choose TWO.)

Accepted Answer

Create a class-map that matches routing protocol packets and assign a police rate with conform-action transmit and violate-action transmit.. Using 'conform-action transmit' and 'violate-action transmit' ensures that routing protocol packets are never dropped, even if they exceed the configured police rate. This prevents CoPP from inadvertently dropping critical control plane traffic during a traffic spike, as the violate-action overrides the default drop behavior. The other correct option, D, uses a high CIR and burst size with 'exceed-action set-dscp cs6' to mark but not drop routing protocol packets, preserving them while still applying QoS treatment.

Answer

Create a class-map that matches routing protocol packets (e.g., OSPF, EIGRP, BGP) and assign a police rate with conform-action transmit and exceed-action drop.

Answer

Place routing protocol traffic into a class with a 'drop' action to prevent it from overwhelming the control plane.

Answer

Apply the CoPP policy only to the 'control-plane host' subinterface, which processes all routing protocol packets.

Question 7

Router R1 has an ACL applied to its VTY lines for SSH access:
access-list 10 permit 10.1.1.0 0.0.0.255
line vty 0 4
 access-class 10 in
 transport input ssh
R1 also has CoPP policy:
class-map match-all SSH-CLASS
 match access-group name SSH-ACL
policy-map COPP
 class SSH-CLASS
  police cir 8000 bc 1500
   conform-action transmit
   exceed-action drop
R2 (10.1.1.2) shows:
R2# ssh -l admin 10.2.2.1
% Connection refused by remote host
R2# telnet 10.2.2.1
Trying 10.2.2.1 ...
% Connection timed out; remote host not responding
What is the root cause?

Accepted Answer

The CoPP policy is rate-limiting SSH traffic from R2, causing drops.. The ACL on VTY lines permits only 10.1.1.0/24, but the SSH connection from R2 (10.1.1.2) should be allowed. However, the CoPP policy is rate-limiting SSH traffic to 8000 bps. If the police rate is exceeded, packets are dropped. The SSH connection might be failing due to CoPP dropping the packets. The telnet is also failing because it is not permitted by the access-class (only SSH is allowed). The root cause is CoPP rate-limiting SSH traffic, causing drops.

Answer

The access-class on VTY lines blocks R2's IP address.

Answer

SSH is not enabled on R1's VTY lines.

Answer

The SSH-ACL in the class-map does not match SSH traffic.

Question 8

Examine the following configuration:

logging host 10.1.1.1
logging host 10.1.1.2
logging host 10.1.1.3
logging origin-id hostname
logging facility local7

What is the purpose of the 'logging origin-id hostname' command?

Accepted Answer

It causes the syslog messages to include the router's hostname as the origin, overriding the default IP address.. The 'logging origin-id' command sets the origin identifier in syslog messages. When set to 'hostname', the router's hostname is used as the origin ID instead of the default (which is the IP address of the source interface). This helps identify the source of messages in a multi-device environment.

Answer

It sets the syslog message format to include the hostname in the timestamp field.

Answer

It configures the router to send syslog messages only when the hostname changes.

Answer

It is used to authenticate syslog messages using the hostname as a key.

Question 9

Drag and drop the steps to verify and validate syslog operational state into the correct order, from first to last.

Accepted Answer

Check logging status with show logging. First, check the logging status with show logging. Then, verify that syslog messages are being sent to the configured server. Next, confirm the severity level of logged messages. After that, validate that the syslog server is receiving messages. Finally, test by generating a test log message.

Question 10

Which TWO commands can be used to verify OSPFv2 path selection and cost metrics on a Cisco IOS router? (Choose TWO.)

Accepted Answer

show ip ospf interface. The 'show ip ospf interface' command displays the cost of the interface. The 'show ip route ospf' command shows the metric for each OSPF route. 'show ip ospf neighbor' does not show cost; 'traceroute' shows path but not OSPF cost; 'show ip protocols' shows process info but not per-route metrics.

Answer

show ip ospf neighbor

Answer

traceroute

Answer

show ip protocols

Question 11

A network engineer runs the following command to troubleshoot OSPF route propagation:

R1# show ip ospf database router 2.2.2.2

OSPF Router with ID (1.1.1.1) (Process ID 1)

Router Link States (Area 0)

LS age: 45
  Options: (No TOS-capability, DC)
  LS Type: Router Links
  Link State ID: 2.2.2.2
  Advertising Router: 2.2.2.2
  LS Seq Number: 80000005
  Checksum: 0x1234
  Length: 48
  Number of Links: 2

Link connected to: a Transit Network
     (Link ID) Designated Router address: 10.1.1.2
     (Link Data) Router Interface address: 10.1.1.2
      Number of TOS metrics: 0
       TOS 0 Metrics: 10

Link connected to: a Stub Network
     (Link ID) Network/subnet number: 192.168.1.0
     (Link Data) Network Mask: 255.255.255.0
      Number of TOS metrics: 0
       TOS 0 Metrics: 10

What does this output indicate?

Accepted Answer

Router 2.2.2.2 has a link to a transit network with DR address 10.1.1.2 and a stub network 192.168.1.0/24.. The output shows the router LSA from neighbor 2.2.2.2, listing its connected links including a transit network and a stub network.

Answer

Router 2.2.2.2 is advertising two stub networks.

Answer

The LSA indicates a Type 5 External LSA from ASBR.

Answer

The output shows the network LSA for the transit network.

Question 12

A network engineer runs the following command on Router R1:

R1# show ip ospf neighbor 10.1.1.2

Neighbor 10.1.1.2, interface address 192.168.12.2
    In the area 0 via interface GigabitEthernet0/0
    Neighbor priority is 1, State is FULL, 6 state changes
    DR is 10.1.1.2, BDR is 10.1.1.1
    Options is 0x12 (L L S R)
    Dead timer due in 00:00:36
    Neighbor is up for 00:15:42
    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 role of Router R1 on this segment?

Accepted Answer

Router R1 is the Backup Designated Router.. The output shows that the BDR is 10.1.1.1, which is Router R1's router ID. Therefore, R1 is the Backup Designated Router. The DR is 10.1.1.2.

Answer

Router R1 is the Designated Router.

Answer

Router R1 is a DROTHER router.

Answer

Router R1 has no special role on this segment.

Question 13

Which OSPF LSA type is used to advertise prefixes from other areas into the backbone area?

Accepted Answer

Type 3 (Summary LSA). Type 3 LSAs (Summary LSAs) are generated by Area Border Routers (ABRs) to advertise networks from one area to another. They are used to propagate inter-area routes.

Answer

Type 1 (Router LSA)

Answer

Type 2 (Network LSA)

Answer

Type 5 (External LSA)

Question 14

A network engineer runs the following command on Router R1:

R1# show policy-map control-plane

Control Plane

Service-policy input: CoPP-IN

Class-map: CoPP-DEFAULT (match-any)
      5000 packets, 300000 bytes
      5 minute offered rate 4000 bps, drop rate 2000 bps
      Match: any
      police:
          cir 32000 bps, bc 6000 bytes, be 6000 bytes
        conformed 3000 packets, 180000 bytes; actions:
          transmit
        exceeded 1000 packets, 60000 bytes; actions:
          drop
        violated 1000 packets, 60000 bytes; actions:
          drop

Based on this output, what is the most likely impact on the router?

Accepted Answer

Some control plane traffic is being dropped, which could cause routing protocol instability.. The output shows that the CoPP policy is policing control plane traffic with a CIR of 32000 bps. The 'exceeded' and 'violated' counters indicate that 2000 packets (120000 bytes) have been dropped, with a drop rate of 2000 bps. This means some control plane traffic is being dropped, which can cause routing protocol instability (e.g., BGP, OSPF keepalives being dropped).

Answer

All control plane traffic is being transmitted without issues.

Answer

The police rate is set to 64000 bps.

Answer

Only ICMP traffic is being dropped.

Question 15

Which TWO symptoms indicate that syslog messages are not being sent to the remote syslog server? (Choose TWO.)

Accepted Answer

The syslog server receives messages from other devices but not from this router.. If syslog messages are not reaching the server, the 'show logging' output will not show the server address as active, and the server will not receive any messages. The 'show logging' command may still show messages in the local buffer. The 'show log' command does not exist. Debug output on the router does not confirm remote delivery.

Answer

The 'show logging' command shows messages in the local buffer.

Answer

The 'show log' command returns no output.

Answer

Debug output appears on the console but not on the syslog server.

Question 16

A network engineer runs the following command on Router R1:

R1# show ipv6 ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
10.1.1.2         1   FULL/BDR        00:00:35    FE80::2          GigabitEthernet0/0
10.1.1.3         1   FULL/DR         00:00:32    FE80::3          GigabitEthernet0/1

Based on this output, which statement is correct regarding OSPFv3?

Accepted Answer

Router R1 has a full adjacency with both neighbors in OSPFv3.. The output shows OSPFv3 neighbors. The neighbor 10.1.1.2 is in state FULL/BDR, meaning it is the Backup Designated Router. The neighbor 10.1.1.3 is in state FULL/DR, meaning it is the Designated Router. The addresses are link-local IPv6 addresses.

Answer

Router R1 is the DR on the segment connected to GigabitEthernet0/0.

Answer

The OSPFv3 process is using IPv4 addresses as router IDs.

Answer

Router R1 is not receiving hello packets from 10.1.1.3.

Question 17

In OSPF, what is the default administrative distance for intra-area routes on a Cisco IOS-XE router?

Accepted Answer

110. Cisco IOS-XE assigns an administrative distance of 110 to all OSPF routes, including intra-area, inter-area, and external routes, unless modified.

Answer

90

Answer

115

Answer

120

Question 18

A network engineer runs the following command on Router R1:

R1# show ipv6 source-guard policy
Interface                      Policy                      Role            State
Gi0/0/0                        SRC_GUARD                   host            ACTIVE
Gi0/0/1                        SRC_GUARD                   host            ACTIVE
Gi0/0/2                        (default)                   host            ACTIVE

Based on this output, which statement is correct?

Accepted Answer

Source guard is enabled on all interfaces, preventing IPv6 address spoofing.. The output shows that Gi0/0/2 uses the (default) policy, which still applies IPv6 source guard with the role 'host' and state 'ACTIVE'. This means source guard is enabled on all three interfaces, preventing IPv6 address spoofing by filtering traffic based on the source address learned via Neighbor Discovery (ND) or DHCPv6.

Answer

Only Gi0/0/0 and Gi0/0/1 have source guard enabled.

Answer

Source guard is disabled on Gi0/0/2 because it uses the default policy.

Answer

Role 'host' means the interface is a router port.

Question 19

What is the default rate-limit interval for the 'logging rate-limit' command in Cisco IOS-XE?

Accepted Answer

1 second. The default rate-limit interval is 1 second, meaning the specified number of messages per second is allowed.

Answer

100 milliseconds

Answer

5 seconds

Answer

No default; it must be specified

Question 20

Consider this OSPF configuration on router R6:

router ospf 1
 network 10.0.0.0 0.255.255.255 area 0
 area 0 stub

What is the effect of the area 0 stub command?

Accepted Answer

The configuration is rejected by IOS because the backbone area cannot be a stub.. The area 0 stub command is invalid because area 0 (the backbone) cannot be configured as a stub area. Stub areas are used to reduce LSA flooding, but the backbone must have full routing information. This configuration will be rejected by IOS.

Answer

Area 0 will become a stub area, blocking type 5 LSAs from entering the backbone.

Answer

The command is ignored, and area 0 remains a normal area.

Answer

Only type 5 LSAs are blocked, but type 3 and 4 LSAs are still allowed.