300-410 Practice Exam 68 — 20 Questions

Question 1

A network engineer runs the following command on Router R1:

R1# show ip eigrp vrf RED neighbors

EIGRP-IPv4 Neighbors for AS(100) VRF RED
H   Address                 Interface              Hold Uptime   SRTT   RTO  Q  Seq
                                                   (sec)         (ms)       Cnt Num
0   192.168.1.2             Gi0/2                   13  00:15:30   12   200  0  45
1   192.168.2.2             Gi0/3                   12  00:14:20   15   200  0  32

Based on this output, what is the problem?

Accepted Answer

The EIGRP adjacency is functioning correctly.. The output shows two EIGRP neighbors for VRF RED. Both are in normal state with low SRTT and no Q count. There is no obvious problem. However, the hold times are 13 and 12 seconds, which are typical. The uptimes are similar. The output is healthy. But if the question implies a problem, it might be that the neighbors are not exchanging routes? But the Seq numbers are incrementing, indicating activity. Actually, no problem is evident. The correct answer should be that the EIGRP adjacency is functioning correctly.

Answer

The EIGRP neighbors are not exchanging routes because the Seq numbers are low.

Answer

Both neighbors are in the Init state.

Answer

The hold time of 13 seconds indicates a problem.

Question 2

A network engineer runs the following command to troubleshoot a VRF-Lite redistribution issue:

R1# debug ip routing vrf CUSTOMER_E

Output:
RT: add 10.3.3.0/24 via 10.1.1.2, ospf 200 metric [110/20]
RT: add 10.3.3.0/24 via 10.1.1.2, eigrp 100 metric [90/131072] tag 0
RT: closer admin distance for 10.3.3.0/24, adding via eigrp 100
RT: add 10.3.3.0/24 to routing table, via eigrp 100

What does this output indicate?

Accepted Answer

The route 10.3.3.0/24 is added from EIGRP 100 because it has a lower administrative distance than OSPF.. The 'debug ip routing vrf' command shows route insertion and selection events for a specific VRF. The output shows that route 10.3.3.0/24 is learned from both OSPF 200 (with administrative distance 110) and EIGRP 100 (with administrative distance 90). Because EIGRP has a lower administrative distance, it is chosen as the best path and added to the routing table.

Answer

The route 10.3.3.0/24 is added from OSPF 200 because it has a lower metric.

Answer

The route 10.3.3.0/24 is added from both OSPF and EIGRP, creating an equal-cost path.

Answer

The route 10.3.3.0/24 is not added to the routing table due to a tag mismatch.

Question 3

A network engineer is troubleshooting a VRF-Lite configuration on a Cisco router. The router has two VRFs (VRF_CUSTOMER_A and VRF_CUSTOMER_B). The engineer notices that traffic from VRF_CUSTOMER_A is being routed to the wrong next-hop, causing connectivity issues. The 'show ip route vrf VRF_CUSTOMER_A' shows a route to the destination via a next-hop that belongs to VRF_CUSTOMER_B. What is the most likely cause?

Accepted Answer

The 'route-target import' command in VRF_CUSTOMER_A is importing routes from VRF_CUSTOMER_B.. This issue is typically caused by route leaking between VRFs, which can happen if the route-target import/export commands are misconfigured or if there is a shared interface with incorrect VRF assignment.

Answer

The router has a default route that points to the next-hop in VRF_CUSTOMER_B.

Answer

The 'ip cef' command is disabled globally.

Answer

The 'ip vrf forwarding' command is applied to the same physical interface for both VRFs.

Question 4

A network engineer runs the following command on Router R1:

R1# show ip vrf interfaces
Interface   VRF          IP Address    Protocol
GigabitEthernet0/0   BLUE         10.1.1.1      up
GigabitEthernet0/1   BLUE         10.1.2.1      up
GigabitEthernet0/2   RED          192.168.1.1   up
Loopback0            BLUE         10.0.0.1      up
Loopback1            RED          192.168.0.1   up

Based on this output, which statement is correct?

Accepted Answer

GigabitEthernet0/2 is in VRF RED with IP address 192.168.1.1.. The 'show ip vrf interfaces' command displays all interfaces assigned to VRFs and their IP addresses. The output shows that GigabitEthernet0/0, GigabitEthernet0/1, and Loopback0 are in VRF BLUE, while GigabitEthernet0/2 and Loopback1 are in VRF RED. There are no interfaces in the global routing table shown here, but that is normal for VRF-Lite.

Answer

All interfaces are in the global routing table.

Answer

Loopback0 is in VRF RED.

Answer

GigabitEthernet0/1 has IP address 10.1.2.2.

Question 5

A network engineer runs the following command on Router R1:

R1# show ip sla summary

IPSLAs Latest Operation Summary

Codes: * active, ^ inactive, ~ pending

ID       Type            Destination       Stats          Return Code      Last
1        icmp-echo       192.168.1.1       RTT=50ms       OK               1s ago
2        icmp-echo       192.168.1.2       RTT=2000ms     Over threshold   2s ago
3        icmp-echo       192.168.1.3       RTT=100ms      OK               3s ago

Based on this output, which statement is correct?

Accepted Answer

IP SLA operation 2 is experiencing high latency, exceeding the configured threshold.. The 'Return Code' column shows 'Over threshold' for ID 2, meaning the RTT exceeded the configured threshold. The other operations are OK. This output does not indicate failure or timeout unless the return code says so.

Answer

IP SLA operation 2 has failed because the destination is unreachable.

Answer

IP SLA operation 1 is not active because it shows 'OK'.

Answer

IP SLA operation 3 has a pending status.

Question 6

A network engineer runs the following command on Router R1:

R1# show ip bgp vpnv4 vrf RED summary

BGP router identifier 192.168.0.1, local AS number 65001
BGP table version is 5, main routing table version 5
4 network entries using 576 bytes of memory
4 path entries using 320 bytes of memory
2/1 BGP path/bestpath attribute entries using 320 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 1216 total bytes of memory
BGP activity 4/0 prefixes, 4/0 paths, scan interval 60 secs

Neighbor        V           AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
10.1.1.2        4        65001      23      25        5    0    0 00:12:34        2
10.1.2.2        4        65002      18      20        5    0    0 00:10:15        1

Based on this output, which statement is correct?

Accepted Answer

Both BGP neighbors are in the Established state.. The 'show bgp vpnv4 vrf RED summary' command displays BGP neighbors for VRF RED. It shows two neighbors: 10.1.1.2 (AS 65001) and 10.1.2.2 (AS 65002). Both are in the Established state with prefixes received. The neighbor 10.1.1.2 has received 2 prefixes, and 10.1.2.2 has received 1 prefix.

Answer

Neighbor 10.1.2.2 is in the Idle state.

Answer

The local AS number is 65002.

Answer

Neighbor 10.1.1.2 is in AS 65002.

Question 7

Consider this partial configuration:
```
ip vrf CUSTOMER_B
 rd 65000:1
 route-target export 65000:1
 route-target import 65000:1
```
What statement is true about this VRF configuration?

Accepted Answer

The VRF is correctly configured for VRF-Lite with a unique RD and optional route-targets.. In VRF-Lite, route-targets are not strictly required because there is no MP-BGP exchange. However, they are used for interoperability and to define import/export policies if needed. The RD is mandatory to create the VRF.

Answer

The VRF will not function because route-targets are mandatory for VRF-Lite.

Answer

The RD must match the route-target value exactly.

Answer

The VRF will only work if 'vrf forwarding' is applied to an interface.

Question 8

A network engineer runs the following command on Router R1:

R1# show ip ospf neighbor vrf BLUE

Neighbor ID     Pri   State           Dead Time   Address         Interface
10.0.0.2          1   FULL/DR        00:00:32    10.1.1.2        GigabitEthernet0/0
10.0.0.3          1   2WAY/DROTHER   00:00:35    10.1.2.2        GigabitEthernet0/1

Based on this output, which statement is correct?

Accepted Answer

The OSPF adjacencies are functioning normally.. The output shows two OSPF neighbors for VRF BLUE. Neighbor 10.0.0.2 is in FULL state and is the DR on GigabitEthernet0/0. Neighbor 10.0.0.3 is in 2WAY state and is a DROTHER on GigabitEthernet0/1. The 2WAY state is normal for neighbors that are not DR/BDR on a multi-access network. No problem is evident.

Answer

Neighbor 10.0.0.3 is not forming a full adjacency because it is a DROTHER.

Answer

Neighbor 10.0.0.2 is the Backup Designated Router.

Answer

Both neighbors are in the FULL state.

Question 9

A network engineer runs the following command on Router R1:

R1# show route-map VRF_RED_MAP
route-map VRF_RED_MAP, permit, sequence 10
  Match clauses:
    ip address prefix-list RED_PREFIXES
  Set clauses:
    tag 100
  Policy routing matches: 0 packets, 0 bytes

Based on this output, what is the problem?

Accepted Answer

The route-map is not applied to any interface.. The route-map VRF_RED_MAP has a match clause for prefix-list RED_PREFIXES and a set clause to tag 100. The policy routing matches show 0 packets, meaning the route-map has never been used. This could indicate that the route-map is not applied to any interface or that no traffic matches the prefix-list.

Answer

The prefix-list RED_PREFIXES is empty.

Answer

The set clause is incorrect.

Answer

The route-map sequence is invalid.

Question 10

Given the following partial configuration on router R1:
```
interface GigabitEthernet0/0
 ip vrf forwarding CUSTOMER_A
 ip address 192.168.1.1 255.255.255.0
```
What is the effect of this configuration?

Accepted Answer

The interface is placed into VRF CUSTOMER_A, and the IP address is assigned correctly.. The 'ip vrf forwarding' command associates the interface with a VRF. It removes the IP address if one was previously configured, requiring it to be re-applied. This ensures traffic on this interface is forwarded using the VRF's routing table.

Answer

The interface is placed into VRF CUSTOMER_A, but the IP address is ignored because it must be configured before the VRF command.

Answer

The VRF name is misspelled; it should be 'vrf forwarding CUSTOMER_A' under the interface.

Answer

The configuration will fail because VRF CUSTOMER_A must be created globally first.

Question 11

A large enterprise network is experiencing intermittent reachability between VRF-A on Router R1 and VRF-B on Router R2. R1 has the following relevant configuration: ip vrf VRF-A, rd 100:1, route-target export 100:1, route-target import 100:2. R2 shows: ip vrf VRF-B, rd 200:2, route-target export 200:2, route-target import 200:1. The link between R1 and R2 is configured with VRF forwarding VRF-A on R1 and VRF forwarding VRF-B on R2. What is the root cause?

Accepted Answer

The route-target import and export values are mismatched between the VRFs, preventing route exchange.. The route-target import/export values are mismatched for the VRF-Lite scenario. In VRF-Lite, route-targets are used for route leaking, but on a direct link, the VRFs must match or route leaking must be configured properly. Here, R1 imports routes with RT 100:2, which R2 exports as 200:2, not 100:2. R2 imports RT 200:1, but R1 exports 100:1. Thus, no routes are exchanged, causing unreachability.

Answer

The RD values must match for VRF-Lite to work on a direct link.

Answer

The VRFs must have the same name on both routers for direct connectivity.

Answer

The interface must be in the same VRF on both ends; route-targets are irrelevant for VRF-Lite.

Question 12

In a VRF-Lite setup using RIP, what is the default update timer value?

Accepted Answer

30 seconds. RIP sends routing updates every 30 seconds by default, as defined in RFC 1058.

Answer

60 seconds

Answer

90 seconds

Answer

180 seconds

Question 13

A network engineer runs the following command on Router R1:

R1# show ip vrf detail RED
VRF RED (VRF Id = 1); default RD <not set>
   Interfaces:
           GigabitEthernet0/2
           Loopback1
   Address family IPV4 (Table ID = 1):
      No Export VPN route-target communities
      No Import VPN route-target communities
      No import route-map
      No export route-map
      VRF label distribution protocol: not configured
   Address family IPV6 (Table ID = 0x1E000001):
      No Export VPN route-target communities
      No Import VPN route-target communities
      No import route-map
      No export route-map
      VRF label distribution protocol: not configured

Based on this output, which statement is correct?

Accepted Answer

The VRF RED includes two interfaces: GigabitEthernet0/2 and Loopback1.. The 'show ip vrf detail RED' command shows detailed VRF information. It lists interfaces GigabitEthernet0/2 and Loopback1. The RD is not set, which is common for VRF-Lite (no MPLS). There are no route-target communities, which is expected for VRF-Lite.

Answer

The VRF RED has a Route Distinguisher configured.

Answer

The VRF RED has an export route-map configured.

Answer

The VRF RED is configured for MPLS label distribution.

Question 14

Which loop prevention mechanism is used by default in RIP within a VRF-Lite configuration?

Accepted Answer

Split horizon. RIP uses split horizon as a default loop prevention mechanism, which prevents a route from being advertised out the interface from which it was learned.

Answer

Route poisoning

Answer

Hold-down timer

Answer

TTL expiry

Question 15

A network engineer is troubleshooting a route filtering issue using distribute-lists under OSPF. Router R8 has a distribute-list out applied to the OSPF process to filter routes being advertised to a specific neighbor. The distribute-list references an ACL that denies a specific prefix, but the prefix is still being advertised to the neighbor. What is the most likely cause?

Accepted Answer

The distribute-list is applied to the OSPF process, not to the specific neighbor; use 'neighbor distribute-list' instead.. Distribute-lists under OSPF can be applied in or out, but the 'out' direction filters routes being advertised out of the OSPF process to all neighbors. However, if the distribute-list is applied to the OSPF process (not to a specific interface), it filters routes from the routing table into OSPF, not to a specific neighbor. To filter per neighbor, a distribute-list must be applied to the neighbor under the OSPF process using 'neighbor x.x.x.x distribute-list'.

Answer

The ACL is using the wrong wildcard mask; it should deny the exact prefix with 0.0.0.0 mask.

Answer

The distribute-list is applied inbound instead of outbound.

Answer

The OSPF process has 'default-information originate' that overrides the distribute-list.

Question 16

A network engineer runs the following command on Router R1:

R1# show ip bgp vpnv4 vrf RED neighbors 10.1.1.2 advertised-routes

BGP table version is 5, local router ID is 192.168.0.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter,
              x best-external, a additional-path, c RIB-compressed,
              t secondary path, L long-lived-stale,
Origin codes: i - IGP, e - EGP, ? - incomplete

Network          Next Hop            Metric LocPrf Weight Path
*> 192.168.1.0/24   0.0.0.0                  0         32768 i
*> 192.168.2.0/24   0.0.0.0                  0         32768 i

Total number of prefixes 2

Based on this output, what is the problem?

Accepted Answer

The routes are being advertised correctly.. The output shows the routes advertised to BGP neighbor 10.1.1.2 for VRF RED. It advertises two networks: 192.168.1.0/24 and 192.168.2.0/24, both with next hop 0.0.0.0 (meaning self). This is normal. However, the next hop 0.0.0.0 might be problematic if the neighbor expects a valid next hop. But in BGP, 0.0.0.0 is used for locally originated routes. The problem could be that the routes are not being advertised with the correct next hop, but for VRF-Lite, this is typical. Actually, no problem is evident. The correct answer might be that the routes are being advertised correctly.

Answer

The routes are advertised with next hop 0.0.0.0, which will cause the neighbor to drop them.

Answer

The BGP table version is 5, indicating a problem.

Answer

The routes have weight 0, which is incorrect.

Question 17

A network engineer runs the following command on Router R1:

R1# show ip route vrf RED 192.168.1.0

Routing entry for 192.168.1.0/24
  Known via "connected", distance 0, metric 0 (connected, via interface)
  Routing Descriptor Blocks:
  * directly connected, via GigabitEthernet0/2
      Route metric is 0, traffic share count is 1

Based on this output, which statement is correct?

Accepted Answer

The route is directly connected via GigabitEthernet0/2.. The output shows the route for 192.168.1.0/24 in VRF RED is a connected route via GigabitEthernet0/2. This is normal.

Answer

The route is learned via OSPF.

Answer

The route is a static route.

Answer

The route has a metric of 1.

Question 18

A network engineer runs the following command to troubleshoot a VRF-Lite issue:

R1# show ip route vrf CUSTOMER_A summary

Output:
IP routing table name: CUSTOMER_A (0x00000001)
IP routing table maximum-paths: 32
Route Source    Networks    Subnets     Replicates  Overhead    Memory (bytes)
connected       2           0           0           0           576
static          1           0           0           0           288
eigrp 100       3           0           0           0           864
  Internal      3       0       0       0       864
  External      0       0       0       0       0
ospf 200        0           0           0           0           0
  Intra-area    0       0       0       0       0
  Inter-area    0       0       0       0       0
  External-1    0       0       0       0       0
  External-2    0       0       0       0       0
  NSSA-1        0       0       0       0       0
  NSSA-2        0       0       0       0       0
bgp 65000       0           0           0           0           0
  Internal      0       0       0       0       0
  External      0       0       0       0       0
Total           6           0           0           0           1728

What does this output indicate?

Accepted Answer

The VRF CUSTOMER_A has 6 routes, with EIGRP 100 providing 3 internal routes.. The 'show ip route vrf summary' command displays the routing table summary for a specific VRF. It shows the number of routes from each routing protocol source. In this output, the VRF CUSTOMER_A has 6 total routes: 2 connected, 1 static, and 3 from EIGRP 100. OSPF and BGP have 0 routes, indicating they are not contributing to the VRF's routing table.

Answer

The VRF CUSTOMER_A has 6 routes, all redistributed from BGP 65000.

Answer

The VRF CUSTOMER_A has 6 routes, with OSPF 200 providing 3 external routes.

Answer

The VRF CUSTOMER_A has 6 routes, all from connected and static only.

Question 19

In a VRF-Lite environment running EIGRP, what is the default hello timer value on a Frame Relay multipoint interface?

Accepted Answer

60 seconds. By default, EIGRP uses a hello timer of 60 seconds on NBMA networks with bandwidth less than T1, including Frame Relay multipoint interfaces, and 5 seconds on high-speed NBMA links.

Answer

5 seconds

Answer

10 seconds

Answer

30 seconds

Question 20

A network engineer runs the following command to troubleshoot a VRF-Lite MPLS LDP issue:

R1# show mpls ldp bindings vrf CUSTOMER_F

Output:
  lib entry: 10.4.4.0/24, rev 2
    local binding:  label: 16
    remote binding: lsr: 2.2.2.2:0, label: 20
  lib entry: 10.5.5.0/24, rev 3
    local binding:  label: 17
    remote binding: lsr: 2.2.2.2:0, label: 21

What does this output indicate?

Accepted Answer

The VRF CUSTOMER_F has two prefixes with local labels 16 and 17, and remote labels 20 and 21 from LSR 2.2.2.2.. The 'show mpls ldp bindings vrf' command displays MPLS label bindings for a specific VRF. The output shows two prefixes (10.4.4.0/24 and 10.5.5.0/24) with local labels (16 and 17) and remote labels (20 and 21) from LSR 2.2.2.2. This indicates that LDP has successfully exchanged labels for these prefixes within the VRF.

Answer

MPLS LDP has not established a session with the remote LSR 2.2.2.2.

Answer

The labels are not being used because the VRF is not configured correctly.

Answer

The remote LSR is using the same labels as the local router.