Home » SWITCH 642-813 Q&As » Section 1 - VLAN » 642-813 Q&A – Implement VLAN based solution (11-15)

642-813 Q&A – Implement VLAN based solution (11-15)

Section 1 – Implement VLAN based solution, given a network design and a set of requirements

VTP is configured on switch R1. Which of the following features were added in VTP version 2 that were not previously supported in VTP version 1? (Select two)
A. Supports Token Ring VLANs.
B. Allows VLAN consistency checks.
C. Saves VLAN configuration memory.
D. Reduces the amount of configuration necessary.
E. Allows active redundant links when used with spanning tree.

Answer: A,B
VTP Version 2 includes the following improvements: Token Ring VLAN support, TLV support, transparent mode, and Consistency checks.
Incorrect Answers:
C: These were not improvements added to VTP Version 2.
D: These were not improvements added to VTP Version 2.
E: STP detects and prevents loops by logically disabling the redundant path ports so there are no active redundant links.

Which three statements are true regarding the above diagram? (Choose three.)

A. DTP packets are sent from Switch B.
B. The native VLAN for Switch B is vlan 1.
C. A trunk link will be formed.
D. DTP is not running on Switch A.
E. Only VLANs 1-1001 will travel across the trunk link.
Answer: A,B,C
You can manually configure trunk links on Catalyst switches for either ISL or 802.1Q mode. In addition, Cisco has implemented a proprietary, point-to-point protocol called Dynamic Trunking Protocol (DTP) that negotiates a common trunking mode between two switches. The negotiation covers the encapsulation (ISL or 802.1Q) as well as whether the link becomes a trunk at all.
You can configure the trunk encapsulation with the switchport trunk encapsulation command, as one of the following: isl – VLANs are tagged by encapsulating each frame using the Cisco ISL protocol. dot1q -VLANs are tagged in each frame using the IEEE 802.1Q standard protocol. The only exception is the native VLAN, which is sent normally and not tagged at all. negotiate (the default)-The encapsulation is negotiated to select either ISL or IEEE 802.1Q, whichever is supported by both ends of the trunk. If both ends support both types, ISL is favored. (The Catalyst 2950 switch does not support ISL encapsulation.)
In the switchport mode command, you can set the trunking mode to any of the following: trunk –
This setting places the port in permanent trunking mode. The corresponding switch port at the other end of the trunk should be similarly configured because negotiation is not allowed. You should also manually configure the encapsulation mode. dynamic desirable (the default)-The port actively attempts to convert the link into trunking mode. If the far-end switch port is configured to trunk , dynamic desirable , or dynamic auto mode, trunking is successfully negotiated. Dynamic auto -The port converts the link into trunking mode. If the far-end switch port is configured to trunk or dynamic desirable , trunking is negotiated. Because of the passive negotiation behavior, the link never becomes a trunk if both ends of the link are left to the dynamic auto default.

The Company network administrator needs to enable VTP pruning within the Company network.
What action should a network administrator take to enable VTP pruning on an entire management domain?
A. Enable VTP pruning on any switch in the management domain
B. Enable VTP pruning on any client switch in the domain
C. Enable VTP pruning on a VTP server in the management domain
D. Enable VTP pruning on every switch in the domain
E. None of the other alternatives apply
Answer: C
The default behavior of a switch is to propagate broadcast and unknown packets across the network. This behavior results in a large amount of unnecessary traffic crossing the network.
VTP pruning increases bandwidth efficiency by reducing unnecessary flooding of traffic, such as broadcast, multicast, unknown, and flooded unicast packets. VTP pruning increases available bandwidth by restricting flooded traffic to those trunk links that the traffic must use to access the appropriate network devices. By default, VTP pruning is disabled.
Enabling VTP pruning on a VTP server enables pruning for the entire management domain. VTP pruning takes effect several seconds after it is enabled. By default, VLANs 2 through 1000 or 2 through 1001 are pruning eligible, depending upon the platform. VTP pruning does not prune traffic from VLANs that are pruning ineligible. VLAN 1 is always pruning ineligible and VLAN 1 cannot be removed from a trunk. However, the "VLAN 1 disable on trunk" feature available on Catalyst 4000, 5000, and 6000 family switches enables the pruning of user traffic, but not protocol traffic such as CDP and VTP, for VLAN 1 from a trunk. Use the vtp pruning command to make VLANs pruning eligible on a Cisco IOS-based switch.
Switch( vlan)# vtp pruning
Once pruning is enabled, use the switchport trunk pruning command to make a specific VLAN pruning ineligible.
Switch( config)# interface fastethernet 0/3
Switch(config-if)# switchport trunk pruning vlan remove vlan 5

The Company switches have all been upgraded to use VTP version 2. What are two benefits provided in VTP Version 2 that are not available in VTP Version 1? (Select two)
A. VTP version 2 supports Token Ring VLANs
B. VTP version 2 allows VLAN consistency checks
C. VTP version 2 allows active redundant links when used with spanning tree
D. VTP version 2 reduces the amount of configuration necessary
E. VTP version 2 saves VLAN configuration memory
Answer: A,B
Understanding VTP Version 2
If you use VTP in your network, you must decide whether to use VTP version1 or version2.
If you are using VTP in a Token Ring environment, you must use version2. VTP version 2 supports the following features not supported in version1:
Token Ring support-VTP version2 supports Token Ring LAN switching and VLANs (Token Ring Bridge Relay Function [TrBRF] and Token Ring Concentrator Relay Function [TrCRF]). Unrecognized Type-Length-Value (TLV) Support-A VTP server or client propagates configuration changes to its other trunks, even for TLVs it is not able to parse. The unrecognized TLV is saved in NVRAM.
Version-Dependent Transparent Mode-In VTP version1, a VTP transparent network device inspects VTP messages for the domain name and version, and forwards a message only if the version and domain name match. Because only one domain is supported in the supervisor engine software, VTP version 2 forwards VTP messages in transparent mode without checking the version.
Consistency Checks-In VTP version 2, VLAN consistency checks (such as VLAN names and values) are performed only when you enter new information through the CLI or SNMP.
Consistency checks are not performed when new information is obtained from a VTP message, or when information is read from NVRAM. If the digest on a received VTP message is correct, its information is accepted without consistency checks.

On switch R1 you issue the "udld enable" global command. What does this command accomplish?
A. Enables all fiber-optic LAN ports for Unidirectional LINK Detection (UDLD)
B. Enables all copper media LAN ports Unidirectional Link Detection (UDLD)
C. Overrides the default UDLS setting for all ports
D. Globally enables all ports on the device for Unidirectional Link Detection (UDLS)
E. None of the other alternatives apply
Answer: A
Enabling UDLD Globally
Beginning in privileged EXEC mode, follow these steps to enable UDLD globally on all fiber-optic interfaces on the switch:
To disable UDLD globally on fiber-optic interfaces, use the no udld enable global configuration command.