Q241. Refer to the exhibit.
Which statement about the topology is true?
A. It provides a transparent LAN service.
B. It provides only point-to-multipoint connections between UNIs.
C. It uses port-based connections at the hub.
D. It provides point-to-point connections between UNIs.
Answer: D
Q242. Which IPv6 prefix is used for 6to4 tunnel addresses?
A. 2001::/23
B. 2002::/16
C. 3ffe::/16
D. 5f00::/8
E. 2001::/32
Answer: B
Explanation:
6to4 works by taking advantage of a reserved IPv6 prefix, 2002::/16. A 6to4 tunnel interface automatically converts the 32 bits in its IPv6 address following this prefix to a global unicast IPv4 address for transport across an IPv4 network such as the public Internet.
Reference: http://packetlife.net/blog/2010/mar/15/6to4-ipv6-tunneling/
Q243. Refer to the exhibit.
Which feature can R1 use to fail over from R2 to R3 if the address for R2 becomes unavailable?
A. object tracking
B. HSRP
C. GLBP
D. LACP
Answer: A
Explanation:
The object tracking feature allows you to create a tracked object that multiple clients can use to modify the client behavior when a tracked object changes. Several clients register their interest with the tracking process, track the same object, and take different actions when the object state changes.
Clients include the following features:
. Embedded Event Manager (EEM)
. Gateway Load Balancing Protocol (GLBP)
. Hot Standby Redundancy Protocol (HSRP)
. Virtual port channel (vPC)
. Virtual Router Redundancy Protocol (VRRP)
The object tracking monitors the status of the tracked objects and communicates any changes made to interested clients. Each tracked object is identified by a unique number that clients can use to configure the action to take when a tracked object changes state.
Reference: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/5_x/nx-os/unicast/configuration/guide/l3_cli_nxos/l3_object.html
Q244. DRAG DROP
Drag and drop the NetFlow Export feature on the left to the NetFlow version that first supported it on the right.
Answer:
Q245. A configuration includes the line ip nbar port-map SSH tcp 22 23 443 8080. Which option describes the effect of this configuration line?
A. It configures NBAR to search for SSH using ports 22, 23, 443, and 8080.
B. It configures NBAR to allow SSH connections only on ports 22, 23, 443, and 8080.
C. It enables NBAR to inspect for SSH connections.
D. It creates a custom NBAR port-map named SSH and associates TCP ports 22, 23, 443, and 8080 to itself.
Answer: A
Explanation:
The ip nbar-port-map command configures NBAR to search for a protocol or protocol name using a port number other than the well-known port.
Reference: http://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/command/reference/fqos_r/qrfcmd10.pd f
Q246. Which option is the most effective action to avoid packet loss due to microbursts?
A. Implement larger buffers.
B. Install a faster CPU.
C. Install a faster network interface.
D. Configure a larger tx-ring size.
Answer: A
Explanation:
You can't avoid or prevent them as such without modifying the sending host's application/network stack so it smoothes out the bursts. However, you can manage
microbursts by tuning the size of receive buffers / rings to absorb occasional microbursts.
Q247. Which mechanism does Cisco recommend for CE router interfaces that face the service provider for an EVPL circuit with multiple EVCs and multiple traffic classes?
A. HCBWFQ
B. LLQ
C. tail drop
D. WRED
Answer: A
Explanation:
In a simple handoff, packets may be discarded in the service provider network, either because of congestion on a link without an appropriate QoS policy or because of a policer QoS configuration on the service provider network that serves to rate limit traffic accessing the WAN core. To address these issues, QoS on the CE device is applied at a per-port level. A QoS service policy is configured on the outside Ethernet interface, and this parent policy includes a shaper that then references a second or subordinate (child) policy that enables queueing within the shaped rate. This is called a hierarchical CBWFQ (HCBWFQ) configuration.
Reference: http://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/Ethernet_Acces s_for_NG_MAN_WAN_V3-1_external.html
Q248. Which two statements about DHCP snooping are true? (Choose two.)
A. It is implemented on a per-VLAN basis.
B. It filters invalid DHCP messages.
C. The binding database logs trusted and untrusted hosts with leased IP addresses.
D. Interfaces are trusted by default.
E. It uses the LFIB to validate requests from untrusted hosts.
Answer: A,B
Q249. Refer to the exhibit.
Which two configuration changes enable you to log in to the router? (Choose two.)
A. Configure a user name and password on the device.
B. Modify the default login authentication group to use the terminal line password.
C. Remove the terminal line password on the console line.
D. Modify the terminal lines to include transport input none.
E. Configure the terminal lines to use the local user database.
Answer: A,B
Q250. Which three statements about EIGRP and BFD are true? (Choose three.)
A. BFD is independent of the routing protocol, so it can be used as a generic failure detection mechanism for EIGRP.
B. Some parts of BFD can be distributed to the data plane, so it can be less CPU-intensive than reduced timers, which exist wholly at the control plane.
C. Reduced EIGRP timers have an absolute minimum detection timer of 1-2 seconds; BFD can provide sub-second failure detection.
D. BFD is tied to specific routing protocols and can be used for generic fault detection for the OSPF, EIGRP, and BGP routing protocols.
E. BFD is dependent on the EIGRP routing protocol, so it can be used as a specific failure detection mechanism.
F. BFD resides on the control plane, so it is less CPU-intensive than if it resided on the data plane.
Answer: A,B,C
Explanation:
There are several advantages to implementing BFD over reduced timer mechanisms for routing protocols:
. Although reducing the EIGRP, IS-IS, and OSPF timers can result in minimum detection timer of one to two seconds, BFD can provide failure detection in less than one second.
. Because BFD is not tied to any particular routing protocol, it can be used as a generic and consistent failure detection mechanism for EIGRP, IS-IS, and OSPF.
. Because some parts of BFD can be distributed to the data plane, it can be less CPU-intensive than the reduced EIGRP, IS-IS, and OSPF timers, which exist wholly at the control plane.
Reference: http://www.cisco.com/c/en/us/td/docs/ios/12_0s/feature/guide/fs_bfd.html