Q1. Which three TLVs does LLDP use to discover network devices? (Choose three.)
A. Management address
B. Port description
C. Network policy
D. System name
E. Location information
F. Power management
Answer: A,B,D
Explanation:
Basic Management TLV Set
This set includes the following five TLVs used in LLDP:
. Port description TLV: Provides a description of the port in an alpha-numeric format. The value equals the ifDescr object, if the LAN device supports RFC 2863.
. System name TLV: Provides the system's assigned name in an alpha-numeric format. The value equals the sysName object, if the LAN device supports RFC 3418.
. System description TLV: Provides a description of the network entity in an alpha-numeric format. This includes system's name and versions of hardware, operating system and networking software supported in the device. The value equals the sysDescr object, if the LAN device supports RFC 3418.
. System capabilities TLV: Indicates the primary function(s) of the device and whether or not these functions are enabled in the device. The capabilities are indicated by two octects. Bits 0 through 7 indicate Other, Repeater, Bridge, WLAN AP, Router, Telephone, DOCSIS cable device and Station respectively. Bits 8 through 15 are reserved.
. Management address TLV: Indicates the addresses of the local LLDP agent. Other remote managers can use this address to obtain information related to the local device.
Reference: http://www.eetimes.com/document.asp?doc_id=1272069
Q2. Two routers are trying to establish an OSPFv3 adjacency over an Ethernet link, but the adjacency is not forming. Which two options are possible reasons that prevent OSPFv3 to form between these two routers? (Choose two.)
A. mismatch of subnet masks
B. mismatch of network types
C. mismatch of authentication types
D. mismatch of instance IDs
E. mismatch of area types
Answer: D,E
Explanation:
An OSPFv3 interface must have a compatible configuration with a remote interface before the two can be considered neighbors. The two OSPFv3 interfaces must match the following criteria:
. Hello interval
. Dead interval
. Area ID
. Optional capabilities
The OSPFv3 header includes an instance ID field to identify that OSPFv3 packet for a particular OSPFv3 instance. You can assign the OSPFv3 instance. The interface drops all OSPFv3 packets that do not have a matching OSPFv3 instance ID in the packet header.
Reference: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/5_x/nx-os/unicast/configuration/guide/l3_cli_nxos/l3_ospfv3.html
Q3. Refer to the exhibit.
A Cisco Catalyst 6500 Series Switch experiences high CPU utilization. What can be the cause of this issue, and how can it be prevented?
A. The hardware routing table is full. Redistribute from BGP into IGP.
B. The software routing table is full. Redistribute from BGP into IGP.
C. The hardware routing table is full. Reduce the number of routes in the routing table.
D. The software routing table is full. Reduce the number of routes in the routing table.
Answer: C
Explanation:
FIB TCAM Exception - If you try to install more routes than are possible into the FIB TCAM you will see the following error message in the logs:
CFIB-SP-STBY-7-CFIB_EXCEPTION : FIB TCAM exception, Some entries will be software switched
%CFIB-SP-7-CFIB_EXCEPTION : FIB TCAM exception, Some entries will be software switched.
%CFIB-SP-STBY-7-CFIB_EXCEPTION : FIB TCAM exception, Some entries will be software switched.
This error message is received when the amount of available space in the TCAM is exceeded. This results in high CPU. This is a FIB TCAM limitation. Once TCAM is full, a flag will be set and FIB TCAM exception is received. This stops from adding new routes to the TCAM. Therefore, everything will be software switched. The removal of routes does not help resume hardware switching. Once the TCAM enters the exception state, the system must be reloaded to get out of that state. You can view if you have hit a FIB TCAM exception with the following command:
6500-2#sh mls cef exception status
Current IPv4 FIB exception state = TRUE
Current IPv6 FIB exception state = FALSE
Current MPLS FIB exception state = FALSE
When the exception state is TRUE, the FIB TCAM has hit an exception.
The maximum routes that can be installed in TCAM is increased by the mls cef maximum-routes command.
Reference: https://supportforums.cisco.com/document/59926/troubleshooting-high-cpu-6500-sup720
Q4. Refer to the exhibit.
While configuring AAA with a local database, users can log in via Telnet, but receive the message "error in authentication" when they try to go into enable mode. Which action can solve this problem?
A. Configure authorization to allow the enable command.
B. Use aaa authentication login default enable to allow authentication when using the enable command.
C. Verify whether an enable password has been configured.
D. Use aaa authentication enable default enable to allow authentication when using the enable command.
Answer: C
Explanation:
If a different enable password is configured, it will override the privilege level 15 of that user and force the existing password to be used for enable access.
Q5. An IP SLA fails to generate statistics. How can you fix the problem?
A. Add the verify-data command to the router configuration.
B. Reload the router configuration.
C. Remove the ip sla schedule statement from the router configuration and re-enter it.
D. Add the debug ip sla error command to the router configuration.
E. Add the debug ip sla trace command to the router configuration.
Answer: A
Q6. Which three statements about the route preference of IS-IS are true? (Choose three.)
A. An L1 path is preferred over an L2 path.
B. An L2 path is preferred over an L1 path.
C. Within each level, a path that supports optional metrics is preferred over a path that supports only the default metric.
D. Within each level of metric support, the path with the lowest metric is preferred.
E. The Cisco IS-IS implementation usually performs equal cost path load balancing on up to eight paths.
F. Both L1 and L2 routes will be installed in the routing table at the same time.
Answer: A,C,D
Explanation:
Given multiple possible routes to a particular destination, an L1 path is preferred over an L2 path. Within each level, a path that supports the optional metrics is preferred over a path that supports only the default metric. (Again, Cisco supports only the default metric, so the second order of preference is not relevant to Cisco routers.) Within each level of metric support, the path with the lowest metric is preferred. If multiple equal-cost, equal-level paths are found by the Decision process, they are all entered into the route table. The Cisco IS-IS implementation usually performs equal-cost load balancing on up to six paths.
Reference: http://www.realccielab.org/operation-of-integrated-is-is.html
Q7. The no ip unreachables command is configured on interfaces to protect the control plane of a router.
Which mechanism is impacted by using this command?
A. ICMP redirects
B. path MTU discovery
C. source routing
D. ICMP router discovery protocol
Answer: B
Q8. Which three options are sub-subfields of the IPv4 Option Type subfield? (Choose three.)
A. Option Class
B. GET
C. Copied
D. PUSH
E. Option Number
F. TTL
Answer: A,C,E
Explanation:
Each IP option has its own subfield format, generally structured as shown below. For most options, all three subfields are used. Option Type, Option Length and Option Data.
Reference: http://www.tcpipguide.com/free/t_IPDatagramOptionsandOptionFormat.htm
Q9. DRAG DROP
Drag and drop the SNMP element on the left to the corresponding definition on the right.
Answer:
Q10. In which way does the Bridge Assurance mechanism modify the default spanning-tree behavior in an effort to prevent bridging loops?
A. Received BPDUs are looped back toward the sender to ensure that the link is bidirectional.
B. If BPDUs are no longer received on a port, the switch immediately sends out a TCN BPDU.
C. Extended topology information is encoded into all BPDUs.
D. BPDUs are sent bidirectional on all active network ports, including blocked and alternate ports.
Answer: D