300-410 Practice Test 27 — 15 Questions

Question 1

Which TWO commands verify the operational status of a local SPAN session on a Cisco IOS-XE switch? (Choose TWO.)

Accepted Answer

show monitor session 1. The 'show monitor session 1' command displays details of a specific SPAN session, including source and destination interfaces and operational state. The 'show monitor' command lists all configured SPAN sessions and their status. 'show spanning-tree' is unrelated, 'show interfaces' does not show SPAN status, and 'show vlan' is for VLAN information.

Answer

show spanning-tree

Answer

show interfaces

Answer

show vlan

Question 2

Which THREE commands are used to troubleshoot a SPAN session on a Cisco Catalyst switch? (Choose THREE.)

Accepted Answer

show monitor session 1. 'show monitor session 1' provides details of the session. 'show monitor' lists all sessions. 'debug monitor' enables debugging for SPAN operations. 'show running-config | include monitor' shows the configuration but is not a direct troubleshooting command for operational issues. 'show ip interface brief' shows IP status, not SPAN.

Answer

show running-config | include monitor

Answer

show ip interface brief

Question 3

A network engineer is troubleshooting an MPLS L3VPN where CE1 (192.168.1.0/24) cannot reach CE2 (192.168.2.0/24). The PE routers are running OSPF with the CEs. On PE1, the VRF configuration includes route-target import and export 100:100. The show ip vrf detail command on PE1 shows the VRF is active, but the CE1 loopback is not present in the VRF routing table. The show ip route vrf CUSTOMER command on PE1 shows only directly connected interfaces. What is the most likely cause?

Accepted Answer

The OSPF process on PE1 is not configured under the VRF.. The CE routes are not being learned via OSPF into the VRF because OSPF process is not associated with the VRF. Without the 'router ospf vrf ' command, OSPF runs in the global routing table and does not populate the VRF.

Answer

The route-target import on PE1 is misconfigured.

Answer

The CE1 interface is not in the VRF.

Answer

The MP-BGP session between PE1 and PE2 is down.

Question 4

Drag and drop the steps to configure and schedule an IP SLA ICMP-echo operation into the correct order, from first to last.

Accepted Answer

Enter IP SLA configuration mode using 'ip sla 1'. The correct order begins by entering IP SLA configuration mode, then defining the ICMP-echo operation with target and source, setting optional parameters like frequency, scheduling the operation to start immediately or at a specific time, and finally verifying the configuration with show commands.

Question 5

A network engineer configures a DHCP snooping trusted port on a switch to allow a legitimate DHCP server. However, clients connected to untrusted ports on the same VLAN cannot obtain IP addresses. The DHCP server is reachable and the switch shows no DHCP snooping drops. Which is the most likely explanation?

Accepted Answer

The DHCP server is not configured to trust the relay agent information option (option 82), causing it to discard the requests.. When DHCP snooping is enabled, the switch inserts the relay agent information option (option 82) into DHCP requests received on untrusted ports. If the DHCP server is not configured to trust or process option 82, it will discard these requests, preventing clients from obtaining IP addresses even though the switch reports no drops. This is the most likely cause because the DHCP server is reachable and the switch shows no drops, indicating the issue lies with how the server handles the relayed packets.

Answer

The trusted port is in the wrong VLAN; DHCP snooping only works when the trusted port is in the same VLAN as the clients.

Answer

The switch has 'ip dhcp snooping verify mac-address' enabled, causing MAC address mismatches.

Answer

The DHCP server is not configured with the correct subnet for the client VLAN.

Question 6

What is the default behavior of EIGRP auto-summary in IOS-XE 15.x and later?

Accepted Answer

Auto-summary is disabled by default. In IOS-XE 15.x and later, EIGRP auto-summary is disabled by default. This change was introduced to align with modern network designs that require classless routing and to prevent unintended route summarization at classful boundaries, which can cause routing loops or suboptimal path selection in discontiguous networks.

Answer

Auto-summary is enabled by default

Answer

Auto-summary is enabled only for connected routes

Answer

Auto-summary is disabled only for point-to-point links

Question 7

What is the default SNMPv3 security level for a user configured with the "snmp-server user username groupname v3 auth sha password" command?

Accepted Answer

authNoPriv. When you configure an SNMPv3 user with the `snmp-server user username groupname v3 auth sha password` command without explicitly specifying a privacy (encryption) password or the `priv` keyword, the default security level is `authNoPriv`. This means authentication is enabled using SHA, but no encryption is applied to the SNMP packets. The security level is implicitly set to `authNoPriv` because the command includes an authentication password but omits the privacy password.

Answer

noAuthNoPriv

Answer

authPriv

Answer

The command is invalid without specifying a security level.

Question 8

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

Accepted Answer

40 seconds. On an Ethernet broadcast network, OSPF defaults to a hello interval of 10 seconds and a dead interval of 40 seconds (four times the hello interval). This is defined in RFC 2328 and is the standard for broadcast multiaccess networks like Ethernet. Option C is correct because the dead interval is explicitly 40 seconds in this scenario.

Answer

10 seconds

Answer

30 seconds

Answer

120 seconds

Question 9

A PE router has the following configuration:

ip vrf CUSTOMER-D
 rd 300:1
 route-target export 300:1
 route-target import 300:1
!
interface GigabitEthernet0/4
 ip vrf forwarding CUSTOMER-D
 ip address 10.3.3.1 255.255.255.252
!
router bgp 65000
 neighbor 10.0.0.1 remote-as 65000
 neighbor 10.0.0.1 update-source Loopback0
!
 address-family vpnv4
  neighbor 10.0.0.1 activate
  neighbor 10.0.0.1 send-community extended
 exit-address-family
!
 address-family ipv4 vrf CUSTOMER-D
  neighbor 10.3.3.2 remote-as 65002
  neighbor 10.3.3.2 activate
 exit-address-family

What is the effect of this configuration?

Accepted Answer

The PE will successfully exchange VPNv4 routes with the remote PE and redistribute routes from CE into VPNv4.. The configuration is correct. The VRF has RD and RTs, the interface is in the VRF, the iBGP VPNv4 session is configured with extended community, and the eBGP session to the CE is configured under the VRF address-family. The PE will exchange VPNv4 routes with the remote PE and redistribute CE routes.

Answer

The eBGP session will fail because the neighbor is not activated under the global BGP process.

Answer

The VPNv4 session will fail because the neighbor is not configured as a route-reflector client.

Answer

The VRF will not import routes because the import and export RTs are the same.

Question 10

Which of the following statements about MPLS L3VPN label operations is true?

Accepted Answer

The ingress PE pushes two labels: the outer IGP label and the inner VPN label.. In MPLS L3VPN, the PE router assigns a per-VRF label (VPN label) for each prefix in the VRF. When forwarding a packet from the CE, the ingress PE pushes an IGP label (for the egress PE) and the VPN label. The egress PE pops the IGP label and uses the VPN label to identify the VRF and forward to the correct CE.

Answer

The egress PE uses the IGP label to determine the VRF.

Answer

The P routers swap the VPN label as they forward the packet.

Answer

The ingress PE pushes only one label (the VPN label) and uses the IP destination for forwarding.

Question 11

A network engineer runs the following command to troubleshoot an Administrative Distance issue:

R1# show ip ospf interface detail GigabitEthernet0/0
GigabitEthernet0/0 is up, line protocol is up
  Internet Address 10.1.1.1/24, Area 0, Attached via Network Statement
  Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1
  Topology-MTID    Cost    Disabled    Shutdown      Topology Name
        0           1        no          no            Base
  Transmit Delay is 1 sec, State DR, Priority 1
  Designated Router (ID) 1.1.1.1, Interface address 10.1.1.1
  Backup Designated router (ID) 2.2.2.2, Interface address 10.1.1.2
  Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
    oob-resync timeout 40
    Hello due in 00:00:03
  Supports Link-local Signaling (LLS)
  Cisco NSF helper support enabled
  IETF NSF helper support enabled
  Can be protected by per-prefix Loop-Free Fast Reroute
  Can be used for per-prefix Loop-Free Fast Reroute remote-LFA tunnels
  Index 1/1/1, flood queue length 0
  Next 0x0(0)/0x0(0)/0x0(0)
  Last flood scan length is 1, maximum is 1
  Last flood scan time is 0 msec, maximum is 0 msec
  Neighbor Count is 1, Adjacent neighbor count is 1
    Adjacent with neighbor 2.2.2.2  (Backup Designated Router)
  Suppress hello for 0 neighbor(s)

What does this output indicate?

Accepted Answer

The interface is an OSPF broadcast interface with a cost of 1, and the router is the Designated Router.. The output shows detailed OSPF interface information, including the cost, timers, and neighbor state. It does not directly show administrative distance, but it is relevant for understanding OSPF operation.

Answer

The interface has an administrative distance of 110.

Answer

The neighbor 2.2.2.2 is not fully adjacent because it is a backup designated router.

Answer

The OSPF process ID is 100.

Question 12

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

R1# show bgp neighbors 10.0.0.2 received-routes

Output:
BGP table version is 10, local router ID is 10.0.0.1
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,
Origin codes: i - IGP, e - EGP, ? - incomplete

Network          Next Hop            Metric LocPrf Weight Path
*> 10.3.3.0/24      10.0.0.2                 0    100      0 65000 i
*> 10.4.4.0/24      10.0.0.2                 0    100      0 65000 i

Total number of prefixes 2

What does this output indicate?

Accepted Answer

R1 is receiving two routes from BGP neighbor 10.0.0.2. The show bgp neighbors received-routes command displays routes received from the specified neighbor. Here, R1 has received two prefixes (10.3.3.0/24 and 10.4.4.0/24) from neighbor 10.0.0.2, with next hop 10.0.0.2 and AS path 65000. These are valid and best.

Answer

R1 is advertising two routes to BGP neighbor 10.0.0.2

Answer

R1 has no BGP routes

Answer

R1 is using OSPF to learn these prefixes

Question 13

In an MPLS L3VPN environment using MP-BGP, what is the default value of the BGP keepalive timer on Cisco IOS-XE?

Accepted Answer

60 seconds. The default BGP keepalive timer is 60 seconds, as defined in RFC 4271 and implemented in Cisco IOS-XE.

Answer

30 seconds

Answer

90 seconds

Answer

180 seconds

Question 14

What is the default BGP hold timer value in an MPLS L3VPN deployment on Cisco IOS-XE?

Accepted Answer

180 seconds. The default BGP hold timer is 180 seconds, meaning a peer is declared dead if no keepalive or update is received within that interval.

Answer

60 seconds

Answer

90 seconds

Answer

120 seconds

Question 15

In MPLS L3VPN, what is the default behavior of BGP auto-summary on Cisco IOS-XE?

Accepted Answer

Auto-summary is disabled by default.. BGP auto-summary is disabled by default on Cisco IOS-XE. When enabled, it would summarize subnets to their classful boundary, but this is not default.

Answer

Auto-summary is enabled by default for all BGP sessions.

Answer

Auto-summary is enabled only for iBGP sessions.

Answer

Auto-summary is disabled for eBGP but enabled for iBGP.