Cisco 300-410 Online Practice Questions and Exam Preparation

Cisco 300-410 Online Questions & Answers

• Question 1:

  Refer to the exhibit. The R1 and R2 configurations are:

  

  The neighbor relationship is not coming up.

  Which two sets of configurations bring the neighbors up? (Choose two.)

  A. R2 ip route 10.1.1.2 255.255.255.255 192.168.1.2 router bgp 100 neighbor 10.1.1.2 ttl-security hops 1 neighbor 10.1.1.2 update-source loopback 0
  B. R1 ip route 10.1.1.2 255.255.255.255 192.168.1.2 router bgp 100 neighbor 10.1.1.2 disable-connected-check neighbor 10.1.1.2 update-source loopback0
  C. R2 ip route 10.1.1.1 255.255.255.255 192.168.1.1 router bgp 200 neighbor 10.1.1.1 disable-connected-check neighbor 10.1.1.1 update-source loopback0
  D. R2 ip route 10.1.1.1 255.255.255.255 192.168.1.1 router bgp 200 neighbor 10.1.1.1 ttl-security hops 1 neighbor 10.1.1.1 update-source loopback 0
  B. R1 ip route 10.1.1.2 255.255.255.255 192.168.1.2 router bgp 100 neighbor 10.1.1.2 disable-connected-check neighbor 10.1.1.2 update-source loopback0
  C. R2 ip route 10.1.1.1 255.255.255.255 192.168.1.1 router bgp 200 neighbor 10.1.1.1 disable-connected-check neighbor 10.1.1.1 update-source loopback0

  ---

  The neighbor disable-connected-check command is used to disable the connection verification process for eBGP peering sessions that are reachable by a single hop but are configured on a loopback interface or otherwise configured with a non-directly connected IP address.

• Question 2:

  Which of the following statements is TRUE about the communication occurring between rtrA and rtrB in the given exhibit?

  

  A. The only loopback interface used in the communication is the loopback 0 interface of rtrA.
  B. The only loopback interface used in the communication is the loopback 1 interface of rtrB.
  C. Both loopback 0 and loopback 1 interfaces are used for the communication between rtrA and rtrB.
  D. Neither loopback 0 nor loopback 1 interface is used for the communication between rtrA and rtrB.
  A. The only loopback interface used in the communication is the loopback 0 interface of rtrA.

  ---

  The only loopback interface used in the communication is the loopback 0 interface of rtrA. The configuration on the rtrA router indicates that BGP is enabled on rtrA in the autonomous system number (ASN) 450. The neighbor 131.78.45.2 remote-as 450 command establishes a connection with the rtrB interface having the 131.78.45.2 address. The Gi0/1 interface of rtrB has the address 131.78.45.2, which is directly connected to the Gi0/0 interface (132.78.45.1) of rtrA. The next line, neighbor 131.78.45.2

  update-source loopback 0, specifies that the 131.78.45.2 interface (Gi0/1) of rtrB communicates with the loopback 0 interface on rtrA.

  In the configuration of rtrB, the neighbor 10.144.1.1 remote-as 450 command establishes a neighboring relationship with the interface having the address10.144.1.1. The loopback 0 interface of rtrA has the address 10.144.1.1. The loopback 1 interface on rtrB is assigned an IP address but not used in establishing BGP connections between rtrA and rtrB

  Loopback 1 interface of rtrB only would only be used in the communication between rtrA and rtrB if you configured rtrA and rtrB as follows:

  rtrA(config)#router bgp 450

  rtrA(config-router)# neighbor 131.78.1.1 remote-as 450

  rtrB(config)#router bgp 450

  rtrB(config-router)# neighbor 131.78.45.1 remote-as 450

  rtrB(config-router)# neighbor 131.78.45.1 update-source loopback 1

  Both loopback 0 and loopback 1 interfaces are NOT used for communication between rtrA and rtrB. Only the loopback 0 interface of rtrA is used. Both of the loopback interfaces would be used in the communication between rtrA and rtrB only if you changed the configuration of rtrA and rtrB, as given below:

  rtrA(config)# router bgp 450

  rtrA(config-router)# neighbor 131.78.1.1 remote-as 450

  rtrA(config-router)# neighbor 131.78.1.1 update-source loopback 0

  rtrB(config)#router bgp 450

  rtrB(config-router)# neighbor 10.144.1.1 remote-as 450

  rtrB(config-router)# neighbor 10.144.1.1 update-source loopback 1

  Because the loopback 0 interface of rtrA is used in communication, is incorrect to state that neither loopback 0 nor loopback 1 interface is used. To ensure that neither of the loopback interfaces are be used for communication, you would configure rtrA and rtrB as follows:

  rtrA(config)# router bgp 450

  rtrA(config-router)# neighbor 131.78.45.2 remote-as 450

  rtrB(config)# router bgp 450

  rtrB(config-router)# neighbor 131.78.45.1 remote-as 450

  Objective:

  Layer 3 Technologies

  Sub-Objective:

  Configure and verify eBGP (IPv4 and IPv6 address families)

  References:

  Cisco > Home > Support > Technology Support > IP > IP Routing > Design > Design Technotes > BGP Case Studies > eBGP Multihop

  Cisco > Cisco IOS IP Routing: Protocol-Independent Command Reference > neighbor update-source Cisco > Cisco IOS IP Routing: Protocol-Independent Command Reference > neighbor remote-as

• Question 3:

  Refer to the exhibit.

  

  Redistribution is enabled between the routing protocols, and nowPC2 PC3, and PC4 cannot reach PC1. What are the two solutions to fix the problem? (Choose two.)

  A. Filter RIP routes back into RIP when redistributing into RIP in R2
  B. Filter OSPF routes into RIP from EIGRP when redistributing into RIP in R2
  C. Filter all routes except RIP routes when redistributing into EIGRP in R2.
  D. Filter RIP AND OSPF routes back into OSPF from EIGRP when redistributing into OSPF in R2
  E. Filter all routes except EIGRP routes when redistributing into OSPF in R3.
  A. Filter RIP routes back into RIP when redistributing into RIP in R2
  B. Filter OSPF routes into RIP from EIGRP when redistributing into RIP in R2

  ---

  Even PC2 cannot reach PC1 so there is something wrong with RIP redistribution in R2. Because RIP has higher Administrative Distance (AD) value than OSPF and EIGRP so it will be looped when doing mutual redistribution.

• Question 4:

  What is LDP used for in an LSR?

  A. to allow for a system-wide exchange of labels across MPLS network
  B. to create a label across the PE routers for end-to-end path assignment
  C. to communicate the routes known for a specific interface
  D. to create a database of label bindings that allow for hop-by-hop forwarding
  D. to create a database of label bindings that allow for hop-by-hop forwarding

• Question 5:

  Consider the partial output of the show ip route eigrp command:

  

  Which of the following destination subnets have equally load-balanced routes? (Choose all that apply.)

  A. 172.161.4.47/30
  B. 172.161.11.0/27
  C. 15.200.16.0/24
  D. 15.11.78.0/24
  E. 0.0.0.0/0
  B. 172.161.11.0/27
  C. 15.200.16.0/24
  E. 0.0.0.0/0

  ---

  The 172.161.11.0/27 and 15.200.16.0/24 networks have equally load-balanced routes. A default route, 0.0.0.0/0, has been configured for load balancing as well. These three subnets are each load balanced on multiple routes. The output entry for the 172.161.11.0/27 subnet is as follows:

  D 172.161.11.0/27 [90/1723695] via 10.10.19.45, 00:56:17, S0/1 [90/1723695] via 10.10.19.40, 00:50:58, S0/1

  This subnet can be reached by rtrA through two routes: 10.10.19.45 and 10.10.19.40 next-hop addresses. Both these routes have the same metric (1723695), and so are equally load balanced.

  In the output, the 15.200.16.0/24 subnet has three equal-metric routes: 10.10.78.23, 10.10.19.40, and 10.10.70.41. These three routes are equally used to balance the load from rtrA to the 15.200.16.0/24 subnet.

  The default route 0.0.0.0/0 is load balanced through two interfaces, as shown in the output:

  D*EX 0.0.0.0/0 [170/2645987] via 10.10.70.41, 00:05:12, Ethernet0/0 [170/2645987] via 10.10.70.23, 00:05:12, Ethernet0/0

  This load balancing of the default route could be tested by using traceroute to any IP address not represented in the routing table and verifying the path taken.

  Subnets 172.161.4.47/30 and 15.11.78.0/24 are not participating in load balancing. In the given output, there is a single route (line) for both of these subnets. The rtrA router uses the route through the next-hop 10.10.78.23 to reach the 172.161.4.47/30 destination subnet. Similarly, rtrA uses the next-hop 10.10.70.41 to transmit packets to the 15.11.78.0/24 subnet.

  Objective:

  Layer 3 Technologies

  Sub-Objective:

  Configure and verify EIGRP load balancing

  References:

  Cisco IOS IP Routing: Protocol-Independent Command Reference > show ip route Cisco > Support > Technology Support > IP > IP Routing > Technology Information > Technology Whitepaper > Enhanced Interior Gateway Routing Protocol > Document ID: 16406 > Load Balancing

• Question 6:

  Refer to the exhibit.

  

  An engineer configured route exchange between two different companies for a migration project EIGRP routes were learned in router C but no OSPF routes were learned in router A. Which configuration allows router A to receive OSPF routes?

  A. (config-router-af-topology)#no redistribute ospf 10 match external 1 external 2 metric 1000000 10 255 1 1500
  B. (config-router-af)#redistribute ospf 10 1000000 10 255 1 1500
  C. (config-router-af-topology)#redistribute connected
  D. (config-router-af-topology)#redistribute ospf 10 metric 1000000 10 255 1 1500
  D. (config-router-af-topology)#redistribute ospf 10 metric 1000000 10 255 1 1500

  ---

  IOU6(config-router-af-topology)#redistribute ospf 10 ? match Redistribution of OSPF routes metric Metric for redistributed routes route-map Route map reference

  IOU6(config-router-af-topology)#redistribute ospf 10 metr IOU6(config-router-af-topology)#redistribute ospf 10 metric ? <1-4294967295> Bandwidth metric in Kbits per second

  IOU6(config-router-af-topology)#redistribute ospf 10 metric

• Question 7:

  Which option is the best for protecting CPU utilization on a device?

  A. fragmentation
  B. COPP
  C. ICMP redirects
  D. ICMP unreachable messages
  B. COPP

• Question 8:

  An engineer configured routing between multiple OSPF domains and introduced a routing loop that caused network instability. Which action resolves the problem?

  A. Set a tag using the redistribute command toward a domain and deny inbound in the other domain by a matching tag.
  B. Set a tag using the redistribute command toward a different domain and deny the matching tag when exiting from that domain.
  C. Set a tag using the network command in a domain and use the route-map command to deny the matching tag when exiting toward a different domain.
  D. Set a tag using the network command in a domain and use the route-map command to deny the matching tag when entering into a different domain.
  A. Set a tag using the redistribute command toward a domain and deny inbound in the other domain by a matching tag.

  ---

  Redistribution Rule: Never advertise prefixes from routing protocol X into Y and then back into X.

  Redistribution goes from one protocol (or routing domain) into the other protocol (or routing domain) using the redistribute command.

  It's easier to picture redistribution between different protocols. Answer "A" means something like this:

  router ospf 1

  redistribute eigrp 100 subnets tag 20

  route-map FILTER deny

  match tag 20

  route-map FILTER permit

  router eigrp 100

  redistribute ospf 1 metric 100000 1 255 1 1500 route-map FILTER

  1)redistribute into ospf and set the tag

  2)redistribute into eigrp and match the tag (with action deny)

  Set a tag so, routes originating from a routing domain will not be redistributed back into that domain.

  https://networklessons.com/cisco/ccie-routing-switching/troubleshooting-metric-redistribution

• Question 9:

  The network administrator configured R1 for Control Plane Policing so that the inbound Telnet traffic is policed to 100 kbps. This policy must not apply to traffic coming in from 10.1.1.1/32 and 172.16.1.1/32. The administrator has configured this:

  

  The network administrator is not getting the desired results. Which set of configurations resolves this issue?

  A. no access-list 101 access-list 101 deny tcp host 10.1.1.1 any eq 23 access-list 101 deny tcp host 172.16.1.1 any eq 23 access-list 101 permit ip any any
  B. control-plane no service-policy input PM-CoPP ! interface Ethernet 0/0 service-policy input PM-CoPP
  C. no access-list 101 access-list 101 deny tcp host 10.1.1.1 any eq 23 access-list 101 deny tcp host 172.16.1.1 any eq 23 access-list 101 permit ip any any ! Interface E 0/0 service-policy input PM-CoPP
  D. control-plane no service-policy input PM-CoPP service-policy input PM-CoPP
  A. no access-list 101 access-list 101 deny tcp host 10.1.1.1 any eq 23 access-list 101 deny tcp host 172.16.1.1 any eq 23 access-list 101 permit ip any any

  ---

  Packets that match a deny rule are excluded from that class and cascade to the next class (if one

  exists) for classification. Therefore if we don't want to CoPP traffic from 10.1.1.1/32 and 172.16.1.1/32, we must "deny" them in the ACL.

• Question 10:

  The following access lists are applied to an interface connecting two OSPF routers:

  

  What is the result?

  A. the DR on the link will begin updating
  B. the OSPF adjacency will go down
  C. the last deny statement will fail to log traffic
  D. the list will only permit IPv6 neighbor advertisements
  B. the OSPF adjacency will go down

  ---

  If this list is applied to the interface connecting two OSPF routers, the OSPF adjacency would go down. The deny ip any any log statement will deny the IPv6 link local addresses, which are used for the neighbor discovery process and by OSPF routers to establish neighbor adjacencies when directly connected.

  By default, IPv6 access lists have a deny all at the end that does NOT include those addresses. However, when you set an explicit deny all as shown in the scenario, you will block all traffic that is not specified by an earlier statement in the list.

  The DR on the link, if present, will not begin updating because the adjacency will fail. It will then have no neighbor to update.

  The last deny statement in the scenario will log any traffic it blocks, as indicated by the inclusion of the log keyword.

  The list will NOT permit neighbor advertisements. These are always done in terms of link local addresses, which the explicit deny ip any any log statement at the end will block.

  Objective:

  Infrastructure Security

  Sub-Objective:

  Configure and verify router security features

  References:

  Security Configuration Guide: Access Control Lists, Cisco IOS XE Release 3S > IPv6 Access Control Lists Cisco > Cisco IOS IPv6 Command Reference > ipv6 access-list Cisco > Cisco IOS Security Command Commands M to R > permit (IP) Cisco > Cisco IOS Security Command Commands D to L > deny (IP)