300-410 Practice Test 9 — 10 Questions

Question 1

A network engineer runs the following command on Router R1:

R1# show ip route 192.168.1.0
Routing entry for 192.168.1.0/24
  Known via "ospf 1", distance 110, metric 20, type extern 2, forward metric 100
  Redistributing via ospf 1
  Last update from 10.1.1.2 on GigabitEthernet0/1, 00:00:05 ago
  Routing Descriptor Blocks:
  * 10.1.1.2, from 10.1.1.2, 00:00:05 ago, via GigabitEthernet0/1
      Route metric is 20, traffic share count is 1

Based on this output, what is the problem?

Accepted Answer

The route is being redistributed back into OSPF, which could cause a routing loop if not filtered.. The output shows a route learned via OSPF with type extern 2 and metric 20. The route is also 'Redistributing via ospf 1', meaning this router is redistributing this route back into OSPF. This could cause a routing loop if the route is redistributed back into the same OSPF process from which it was learned. The problem is that the route is being redistributed without filtering, potentially causing loops.

Answer

The route is an external OSPF route with metric 20, which is the default for Type 2 external routes.

Answer

The forward metric is 100, which is the metric to the ASBR.

Answer

The route is learned from neighbor 10.1.1.2, which is the next hop.

Question 2

A network engineer configures a Flexible NetFlow monitor to capture traffic on a router's WAN interface. The flow record includes 'match ipv4 source address', 'match ipv4 destination address', and 'collect counter bytes'. After applying the monitor, 'show flow monitor name MONITOR cache' shows flows, but the collector receives no data. 'show flow exporter name EXPORTER statistics' shows 'Export packets sent: 0'. What is the most likely cause?

Accepted Answer

The flow monitor is not associated with any flow exporter.. A flow exporter must be associated with the flow monitor. If the monitor does not reference the exporter, no data is exported even if flows are cached.

Answer

The flow exporter is configured with the wrong destination IP address.

Answer

The flow exporter is missing the 'source' interface command.

Answer

The flow cache is full, preventing new exports.

Question 3

Which TWO statements about the 'distance' command in Cisco IOS routing protocols are true? (Choose TWO.)

Accepted Answer

Under EIGRP, the 'distance eigrp

' command sets different ADs for internal and external routes.. The distance command can be used to modify the administrative distance for routes learned via a routing protocol. It can be applied globally or with an access-list or prefix-list to match specific routes. The command does not affect the AD of routes from other protocols. The distance value must be between 1 and 255. The command can be used under EIGRP, OSPF, RIP, and BGP, but the syntax varies slightly.

Answer

The 'distance' command can be used to change the AD of connected routes.

Answer

The 'distance' command requires a route-map to match specific prefixes in all routing protocols.

Answer

The 'distance' command can be used to set an AD of 0 for a specific route.

Question 4

OSPF network type mismatch on a multi-access link is causing route summarization issues. Router R1 and R2 are connected via Ethernet, but R1 has:
interface GigabitEthernet0/0
 ip address 10.0.0.1 255.255.255.0
 ip ospf network point-to-point
 ip ospf 1 area 0
!
Router R2 has default OSPF network type (broadcast). R1 is configured with:
router ospf 1
 area 0 range 10.0.0.0 255.255.255.0
!
R2 shows:
R2# show ip ospf neighbor
Neighbor ID     Pri   State           Dead Time   Address         Interface
10.0.0.1          0   FULL/  -        00:00:30    10.0.0.1        GigabitEthernet0/0
But R2 does not have the summary route in its routing table. What is the root cause?

Accepted Answer

R1 is not an ABR (only area 0), so the area range command does not generate a summary route.. The network type mismatch (point-to-point on R1, broadcast on R2) prevents proper adjacency formation. Although the neighbor state shows FULL, the DR/BDR election is affected. R1's point-to-point setting means it does not participate in DR election, and R2 expects a DR. This can cause LSA flooding issues, and the area range summary may not be advertised correctly. The summary route is generated by the ABR, but if R1 is not an ABR (area 0 only), the range command has no effect. The root cause is that R1 is not an ABR, so area range does not apply.

Answer

The network type mismatch causes OSPF to not exchange LSAs correctly, preventing the summary.

Answer

The summary route is suppressed because the interface is point-to-point.

Answer

R2 has a static route that overrides the summary.

Question 5

An enterprise uses EIGRP for IPv6 with route redistribution from a static route. R1 has a static route 2001:db8:0::/32 via Null0 redistributed into EIGRP. R2 receives this route and has a more specific route 2001:db8:1::/32 via a different interface. R2 has an IPv6 ACL applied inbound on the interface facing R1 that permits only EIGRP and denies all other traffic. R2's uRPF is configured in loose mode. Traffic from R2 to 2001:db8:2::1 fails. R2 shows 'show ipv6 route' has both routes, but 'show ipv6 cef' shows the summary route for 2001:db8:2::1 pointing to R1. What is the root cause?

Accepted Answer

The summary route 2001:db8:0::/32 on R1 points to Null0, causing traffic to be dropped at R1.. R1's static route 2001:db8:0::/32 via Null0 is redistributed into EIGRP, and R2 learns this summary route. When R2 sends traffic to 2001:db8:2::1, the CEF table (show ipv6 cef) shows the longest prefix match for 2001:db8:2::1 is the summary 2001:db8:0::/32 pointing to R1, not the more specific 2001:db8:1::/32. R1 then forwards the packet to Null0 (a virtual interface that drops traffic), causing the failure. The more specific route 2001:db8:1::/32 on R2 is not used because 2001:db8:2::1 does not fall within that prefix.

Answer

The ACL on R2 blocks the return traffic from R1, causing asymmetric routing.

Answer

uRPF loose mode drops the packet because the source address is not in the FIB.

Answer

EIGRP redistribution of the static route creates a routing loop between R1 and R2.

Question 6

A network engineer runs the following command to troubleshoot a Control Plane Policing (CoPP) issue:

R1# show policy-map control-plane input class class-default

Class-map: class-default (match-any)
  0 packets, 0 bytes
  5 minute offered rate 0 bps, drop rate 0 bps
  Match: any
  police:
      cir 1000000 bps, bc 31250 bytes, be 31250 bytes
    conformed 0 packets, 0 bytes; actions:
      transmit
    violated 0 packets, 0 bytes; actions:
      drop
    conformed 0 bps, exceed 0 bps, violated 0 bps

What does this output indicate?

Accepted Answer

The CoPP policy is not matching any traffic, indicating a possible ACL or class-map misconfiguration.. The output shows zero packets matched in class-default, meaning no traffic is being classified by the CoPP policy. This indicates a possible misconfiguration in the ACL or class-map that defines the traffic to be policed, causing the policy to be effectively inactive. A correctly configured CoPP policy would show non-zero packet counts for matched traffic.

Answer

The CoPP policy is dropping all traffic due to a misconfigured CIR.

Answer

The CoPP policy is working correctly and policing traffic at 1 Mbps.

Answer

The CoPP policy is only applied to the output direction.

Question 7

A network engineer is troubleshooting an OSPFv2 route flapping issue. The router R1 is learning a route to 192.168.1.0/24 via two different paths: one through R2 and one through R3. The route is flapping between the two paths every few seconds. 'show ip ospf interface' shows that both interfaces are stable. What is the most likely cause?

Accepted Answer

The routers R2 and R3 have the same OSPF router ID.. Route flapping can be caused by a number of issues, but if the interfaces are stable, the problem is likely due to a routing loop or a metric issue. One common cause is that the routers are using the same router ID, causing OSPF to see the same route from two different neighbors as equal-cost paths, but the route may be flapping due to a change in the metric. Another cause is that the link between R1 and R2 is flapping at Layer 1, but the stem says the interfaces are stable. The most likely cause is that the routers have duplicate router IDs, which can cause OSPF to treat the same route as two different routes and cause instability.

Answer

The route is being redistributed by both R2 and R3 with different metrics.

Answer

The OSPF network type on the interfaces is set to broadcast, causing DR/BDR instability.

Answer

The link between R1 and R2 has a high error rate causing intermittent packet loss.

Question 8

A network engineer runs the following command on Router R1:

R1# show ip bgp 10.1.1.0/24
BGP routing table entry for 10.1.1.0/24, version 10
Paths: (1 available, best #1, table default)
  Advertised to update-groups:
     1
  Refresh Epoch 1
  Local
    10.2.2.2 from 10.2.2.2 (2.2.2.2)
      Origin IGP, metric 0, localpref 100, valid, external, best
      rx pathid: 0, tx pathid: 0x0
      Community: 100:200

Based on this output, what is the problem?

Accepted Answer

The route 10.1.1.0/24 is redistributed from an IGP into BGP, as indicated by the 'Local' path.. The output shows a BGP route with 'Local' as the path, meaning it was redistributed into BGP locally. The origin is IGP, and the community is 100:200. The route is valid and best. However, the 'Local' path indicates redistribution from an IGP into BGP, which is common in redistribution scenarios.

Answer

The route 10.1.1.0/24 is learned via an eBGP session and has a local preference of 100.

Answer

The community 100:200 is automatically assigned by BGP for all redistributed routes.

Answer

The route is not being advertised to any peers because it is not marked as best.

Question 9

A network engineer runs the following command on Router R1:

R1# show snmp user

User name: monitor
Engine ID: 800000090300001122334455
storage-type: nonvolatile
Authentication Protocol: MD5
Privacy Protocol: DES
Group-name: readonly

User name: admin
Engine ID: 800000090300AABBCCDDEEFF
storage-type: nonvolatile
Authentication Protocol: SHA
Privacy Protocol: AES256
Group-name: admin

Based on this output, which statement is correct?

Accepted Answer

The 'monitor' user uses deprecated authentication and privacy protocols.. The 'monitor' user is configured with MD5 for authentication and DES for privacy. Both MD5 and DES are considered deprecated in SNMPv3 due to known security vulnerabilities; RFC 3414 defines MD5 as a weaker authentication protocol, and DES (56-bit key) is no longer recommended for encryption. The output confirms these protocols are in use, making option A correct.

Answer

The 'admin' user can only read MIB objects.

Answer

Both users use the same engine ID.

Answer

The 'monitor' user cannot authenticate because MD5 is not supported.

Question 10

A network engineer runs the following command on Router PE2:

PE2# show ip bgp vpnv4 vrf CUSTOMER_A 10.10.10.0 24
BGP routing table entry for 10.10.10.0/24, version 15
Paths: (1 available, best #1, table CUSTOMER_A)
  Advertised to update-groups:
     1          
  Refresh Epoch 1
  Local, imported path from 10.10.10.0/24
    10.1.1.1 (metric 20) from 10.1.1.1 (10.1.1.1)
      Origin incomplete, metric 0, localpref 100, valid, internal, best
      Extended Community: RT:100:100
      mpls labels in/out 18/19

Based on this output, what is the problem?

Accepted Answer

The route is functioning correctly with no issues.. The output shows a VPNv4 route for VRF CUSTOMER_A. The route is marked as 'imported path from 10.10.10.0/24', which indicates it was imported from the global table or another VRF. The route is valid and best, with labels assigned. No problem is indicated; the route is functioning correctly.

Answer

The route is not being advertised to any BGP peer.

Answer

The route is missing the required Route Target community.

Answer

The route has an incorrect label binding.