CCNA Sem 2 Module 5-6
Which spanning tree standard supports only one root bridge so that traffic from all VLANs flows over the same path? Rapid PVST 802.1D MST PVST+
802.1D
During the implementation of Spanning Tree Protocol, all switches are rebooted by the network administrator. What is the first step of the spanning-tree election process?
All switches send out BPDUs advertising themselves as the root bridge
Which statement describes STP? -STP is a layer 2 routing protocol -STP is a layer 3 routing protocol for ethernet LANs -STP is a layer 2 loop prevention protocol for ethernet LANs -STP is a layer 3 loop prevention protocol for IP Networks
STP is a layer 2 loop prevention protocol for ethernet LANs
What is an accurate description of redundancy?
designing a network to use multiple paths between switches to ensure there is no single point of failure
Which statement is true regarding the use of PAgP to create EtherChannels? It requires full duplex. It is Cisco proprietary. It requires more physical links than LACP does. It increases the number of ports that are participating in spanning tree. It mandates that an even number of ports (2, 4, 6, etc.) be used for aggregation
-it is Cisco proprietary
What is a characteristic of spanning tree? It is enabled by default on Cisco switches. It has a TTL mechanism that works at Layer 2. It prevents propagation of Layer 2 broadcast frames. It is used to discover information about an adjacent Cisco device
-it is enabled by default on Cisco switches
A switch is configured to run STP. What term describes the reference point for all path calculations? root bridge root port designated port alternate port
-root bridge
By default (without any configuration on a switch), what will determine which switch is the root bridge?
The MAC address of the switch
A set of switches is being connected in a LAN topology. Which STP bridge priority value will make it least likely for the switch to be selected as the root? 4096 32768 61440 65535
-61440
What are three advantages of using EtherChannel technology? (Choose three.) -A spanning-tree recalculation is not required when a single link within the channel goes down -There is no need to upgrade links to faster connections to increase bandwidth -Load balancing is not needed with EtherChannel -Configuration tasks can be done on the EtherChannel interface -EtherChannel uses multiple logical links to provide redundancy
-A spanning-tree recalculation is not required when a single link within the channel goes down -There is no need to upgrade links to faster connections to increase bandwidth -Configuration tasks can be done on the EtherChannel interface
Which statement describes an EtherChannel implementation? EtherChannel operates only at Layer 2. PAgP cannot be used in conjunction with EtherChannel. A trunked port can be part of an EtherChannel bundle. EtherChannel can support up to a maximum of ten separate links
-A trunked port can be part of an EtherChannel bundle
What will happen if a network administrator puts a port that is part of an EtherChannel bundle into a different VLAN than the other ports in that bundle? -Active -Auto -Passive -Desirable
-Active
During the implementation of Spanning Tree Protocol, all switches are rebooted by the network administrator. What is the first step of the spanning-tree election process? -Each switch with a lower root ID than its neighbor will not send BPDUs. -All the switches send out BPDUs advertising themselves as the root bridge. -Each switch determines the best path to forward traffic. -Each switch determines what port to block to prevent a loop from occurring.
-All the switches send out BPDUs advertising themselves as the root bridge.
Which three interface parameters must match for an EtherChannel to form? (Choose three.) -Spanning-tree state -Allowing VLANs -PortFast Mode -Trunking Mode -EtherChannel Mode -Native VLAN
-Allowing VLANs -Trunking Mode -Native VLAN
Which function is provided by EtherChannel? -Dividing the bandwidth of a single link into seperate time slots -Creating one logical link by using multiple physical links between two LAN Switches -Enabling traffic from multiple VLANs to travel over a single layer 2 link
-Creating one logical link by using multiple physical links between two LAN Switches
Which PAgP interface mode will initiate negotiation with other interfaces? -On -Desirable -Auto
-Desirable
Which three STP port states are merged into the RSTP discarding port state? (Choose three.) -Disabling -Blocking -Learning -Listening -Forwarding
-Disabling -Blocking -Listening
Which statement is true about EtherChannel technology? -STP does not run on redundant EtherChannel links -Links must be upgraded to support EtherChannel -All configuration tasks must be done on the individual ports in the EtherChannel link -EtherChannel uses existing switch ports
-EtherChannel uses existing switch ports
A small company network has six interconnected Layer 2 switches. Currently all switches are using the default bridge priority value. Which value can be used to configure the bridge priority of one of the switches to ensure that it becomes the root bridge in this design? 1 28672 32768 34816 61440
28672, The default bridge priority value for all Cisco switches is 32768. The range is 0 to 61440 in increments of 4096. Thus, the values 1 and 34816 are invalid. Configuring one switch with the lower value of 28672 (and leaving the bridge priority value of all other switches unchanged) will make the switch become the root bridge.
A network administrator is configuring an EtherChannel link between switches SW1 and SW2 by using the command SW1(config-if-range)# channel-group 1 mode auto . Which command must be used on SW2 to enable this EtherChannel? SW2(config-if-range)# channel-group 1 mode on SW2(config-if-range)# channel-group 1 mode active SW2(config-if-range)# channel-group 1 mode passive SW2(config-if-range)# channel-group 1 mode desirable
-SW2(config-if-range)# channel-group 1 mode desirable
Which two load balancing methods can be implemented with EtherChannel technology? (Choose two.) -Destination MAC to Destination IP -Destination IP to Source IP -Destination IP to Destination MAC -Source IP to Destination IP -Source MAC to Destination MAC -Destination MAC to Source MAC
-Source IP to Destination IP -Source MAC to Destination MAC
Which statement describes a characteristic of EtherChannel? It can combine up to a maximum of 4 physical links. It can bundle mixed types of 100 Mb/s and 1Gb/s Ethernet links. It consists of multiple parallel links between a switch and a router. It is made by combining multiple physical links that are seen as one link between two switches
-it is made by combining multiple physical links that are seen as one link between two switches
If no bridge priority is configured in PVST, which criteria is considered when electing the root bridge? lowest IP address lowest MAC address highest IP address highest MAC address
-lowest MAC address
When EtherChannel is configured, which mode will force an interface into a port channel without exchanging aggregation protocol packets? active auto on desirable
-on
What is the purpose of the Spanning Tree Protocol (STP)? prevents Layer 2 loops prevents routing loops on a router creates smaller collision domains creates smaller broadcast domains allows Cisco devices to exchange routing table updates
-prevents layer 2 loops
What are two requirements to be able to configure an EtherChannel between two switches? (Choose two.) The interfaces that are involved need to be contiguous on the switch. All the interfaces need to work at the same speed. All the interfaces need to be working in the same duplex mode. All interfaces need to be assigned to different VLANs. Different allowed ranges of VLANs must exist on each end
All the interfaces need to work at the same speed. All the interfaces need to be working in the same duplex mode.
When a range of ports is being configured for EtherChannel by the use of PAgP, which mode will form the bundled channel only if the port receives PAgP packets from another device? -Desirable -Auto -Active -Passive
Auto
Which combinations of PAgP modes will form an EtherChannel? (Choose all that apply.) -Auto > Desirable -Desirable > On -Auto > On -On > On -On > Passive -Active > Passive
Auto > Desirable On > On
The port on the segment (with two switches) that has the lowest path cost to the root bridge is the:
Designated Port
Which of the following ports will forward Ethernet frames? (Choose two.) -Designated Port -Blocked or Non-dedicated Port -Root Port
Designated Port Root Port
When a range of ports is being configured for EtherChannel, which mode will configure PAgP so that it initiates the EtherChannel negotiation? -Auto -Desirable -Active -Passive
Desirable
Which two mode combinations would result in the successful negotiation of an EtherChannel? (Choose two.) -Auto;Auto -Desirable;Desirable -Passive;Auto -Desirable;Active -Active;On -Active;Passive
Desirable;Desirable Active;Passive
After the election of the root bridge has been completed, how will switches find the best paths to the root bridge?
Each switch will analyze the sum of all port costs to reach the root and use the path with the lowest cost.
How often does a switch send a BPDU? -Every 2 seconds -Every 15 seconds -Every 30 seconds -Only when there is a change in topology
Every 2 seconds
True or False? FastEthernet and GigabitEthernet links can be combined into a single EtherChannel.
False
True or False? PAgP and LACP are both Cisco-proprietary link aggregation protocols.
False
Which port state will switch ports immediately transition to when configured for PortFast? -Learning -Forwarding -Listening -Blocking
Forwarding
When PVST is running over a switched network, which port state can participate in BPDU frame forwarding based on BPDUs received, but does not forward data frames? -Forwarding -Listening -Blocking -Disabled
Listening
The root bridge will be the switch with the: -Lowest Bridge ID -Highest Bridge ID -Lowest Port Priority -Highest Port Priority
Lowest Bridge ID
Which is the default STP operation mode on Cisco Catalyst switches? -VLAN ID -Extended System ID -MAC Address -Bridge Priority
MAC Address
Which is the default STP operation mode on Cisco Catalyst switches? -RSTP -PVST -MSTP -MST -Rapid PVST+
PVST
When EtherChannel is implemented, multiple physical interfaces are bundled into which type of logical connection?
Port channel
Which technology solves the problem of a device being unable to get an IPv4 address from a DHCP server due to STP forwarding delay timers?
PortFast
Which protocol was designed to bring faster convergence to STP?
RSTP (Rapid Spanning Tree Protocol)
The sum of individual port costs along the path from the switch to the root bridge is known as the:
Root Path Cost
The port closest to the root bridge in terms of least overall cost (best path) to the root bridge is the:
Root Port
Which STP port role is adopted by a switch port if there is no other port with a lower cost to the root bridge?
Root Port
Which STP port role is adopted by a switch port if there is no other port with a lower cost to the root bridge? designated port root port alternate disabled port
Root Port
What device is elected by the Spanning Tree Algorithm? All other switches determine a single least-cost path to this device. -Root bridge -Dedicated bridge -Default gateway -Core switch
Root bridge
An EtherChannel link using LACP was formed between two switches, S1 and S2. While verifying the configuration, which mode combination could be utilized on both switches?
S1-Passive and S2-Active
A network administrator is configuring an EtherChannel link between two physical ports on a switch. Which statement describes the result when one of the physical ports fails?
The EtherChannel continues transmitting data with reduced bandwidth
Refer to the exhibit. An EtherChannel was configured between switches S1 and S2, but the interfaces do not form an EtherChannel. What is the problem?
The EtherChannel was not configured with the same allowed range of VLANs on each interface
An administrator is troubleshooting a switch and wants to verify if it is a root bridge. What command can be used to do this?
show spanning-tree
A network administrator has configured an EtherChannel between two switches that are connected via four trunk links. If the physical interface for one of the trunk links changes to a down state, what happens to the EtherChannel? The EtherChannel will transition to a down state. Spanning Tree Protocol will recalculate the remaining trunk links. The EtherChannel will remain functional. Spanning Tree Protocol will transition the failed physical interface into forwarding mode
-the EtherChannel will remain functional
What additional information is contained in the 12-bit extended system ID of a BPDU? -MAC address -VLAN ID -IP address -port ID
VLAN ID
What are two advantages of using LACP? (Choose two.) LACP allows Fast Ethernet and Gigabit Ethernet interfaces to be mixed within a single EtherChannel. It eliminates the need for configuring trunk interfaces when deploying VLANs on multiple switches. It allows directly connected switches to negotiate an EtherChannel link. It provides a simulated environment for testing link aggregation. It decreases the amount of configuration that is needed on a switch. It allows the use of multivendor devices
-It allows directly connected switches to negotiate an EtherChannel link -It allows the use of multivendor devices
Which technology is an open protocol standard that allows switches to automatically bundle physical ports into a single logical link? Multilink PPP DTP LACP PAgP
-LACP
Which three port states are used by Rapid PVST+? (Choose three.) -Trunking -Learning -Blocking -Listening -Forwarding -Discarding
-Learning -Forwarding -Discarding
Which protocol provides up to 16 instances of RSTP, combines many VLANs with the same physical and logical topology into a common RSTP instance, and provides support for PortFast, BPDU guard, BPDU filter, root guard, and loop guard? STP Rapid PVST+ PVST+ MST
-MST
What is one way to correct a spanning tree failure? -Replace all instances of STP with RSTP -Replace all cables on failed STP links -Manually remove redundant links in the switched Network -Insert redundant links to replace the failed STP links
-Manually remove redundant links in the switched Network
Without STP on the Ethernet LAN, which three types of frames could cause a catastrophic loop in the network? (Choose three.) -Multicast -Unicast -Unknown Unicast -Broadcast
-Multicast -Unknown Unicast -Broadcast
What is the outcome of a Layer 2 broadcast storm? Routers will take over the forwarding of frames as switches become congested. New traffic is discarded by the switch because it is unable to be processed. CSMA/CD will cause each host to continue transmitting frames. ARP broadcast requests are returned to the transmitting host
-New traffic is discarded by the switch because it is unable to be processed
Which three are PAgP interface modes? (Choose three.) -On -Active -Passive -Auto -Desirable
-On -Auto -Desirable
When a range of ports is being configured for EtherChannel, which mode will configure LACP so that it initiates the EtherChannel negotiation? -RSTP -STP -PAgp -EtherChannel -802.3ad
-PAgP -802.3ad
When a range of ports is being configured for EtherChannel, which mode will configure LACP on a port only if the port receives LACP packets from another device? -Auto -Active -Passive -Desirable
-Passive
Which two concepts relate to a switch port that is intended to have only end devices attached and intended never to be used to connect to another switch? (Choose two.) -PortFast -Bridge ID -Edge Port -Extended System ID -PVST+
-PortFast -Edge Port
Which mode configuration setting would allow formation of an EtherChannel link between switches SW1 and SW2 without sending negotiation traffic? SW1: onSW2: on SW1: desirableSW2: desirable SW1: autoSW2: autotrunking enabled on both switches SW1: autoSW2: autoPortFast enabled on both switches SW1: passiveSW2: active
-SW1: on SW: on
What are two drawbacks to turning spanning tree off and having multiple paths through the Layer 2 switch network? (Choose two.) The switch acts like a hub. Port security becomes unstable. The MAC address table becomes unstable. Broadcast frames are transmitted indefinitely. Port security shuts down all of the ports that have attached devices
-The MAC address table becomes unstable. -Broadcast frames are transmitted indefinitely
A network administrator configured an EtherChannel link with three interfaces between two switches. What is the result if one of the three interfaces is down? The EtherChannel fails. The remaining two interfaces continue to load balance traffic. The remaining two interfaces become separate links between the two switches. One interface becomes an active link for data traffic and the other becomes a backup link
-The remaining two interfaces continue to load balance traffic
Which two statements describe a switch port that is configured with PortFast? (Choose two.) -The switch port should never receive BPDUs -The switch port immediately transitions from the blocking to the forwarding state -The switch port immediately transitions from the listening to the forwarding state -The switch port sends DHCP requests before transitioning to the forwarding state
-The switch port should never receive BPDUs -The switch port immediately transitions from the blocking to the forwarding state
What additional information is contained in the 12-bit extended system ID of a BPDU? -IP Address -MAC Address -VLAN ID -Port ID
-VLAN ID
Refer to the exhibit. What are the possible port roles for ports A, B, C, and D in this RSTP-enabled network? alternate, root, designated, root designated, root, alternate, root alternate, designated, root, root designated, alternate, root, root
-alternate,designated,root,root
A switch is configured to run STP. What term describes a field that has a default value of 32,768 and is the initial deciding factor when electing a root bridge? bridge priority BPDUs bridge ID extended system ID
-bridge priority
A switch is configured to run STP. What term describes a field that has a default value of 32,768 and is the initial deciding factor when electing a root bridge? bridge priority MAC Address extended system ID bridge ID
-bridge priority
What is the value used to determine which port on a non-root bridge will become a root port in a STP network? the highest MAC address of all the ports in the switch the lowest MAC address of all the ports in the switch the VTP revision number the path cost
-the path cost
What are two advantages of EtherChannel? (Choose two.) Configuring the EtherChannel interface provides consistency in the configuration of the physical links. Load balancing occurs between links configured as different EtherChannels. EtherChannel uses upgraded physical links to provide increased bandwidth. Spanning Tree Protocol views the physical links in an EtherChannel as one logical connection. Spanning Tree Protocol ensures redundancy by transitioning failed interfaces in an EtherChannel to a forwarding state
-configuring the EtherChannel interface provides consistency in the configuration of the physical links -spanning tree protocol views the physical links in an etherchannel as on logical connection
When the show spanning-tree vlan 33 command is issued on a switch, three ports are shown in the forwarding state. In which two port roles could these interfaces function while in the forwarding state? (Choose two.) disabled designated root alternate blocked
-designated -root
A switch is configured to run STP. What term describes a non-root port that is permitted to forward traffic on the network? designated port alternate port disabled root port
-designated port
Which two channel group modes would place an interface in a negotiating state using PAgP? (Choose two.) on desirable active auto passive
-desirable -auto
Which two concepts relate to a switch port that is intended to have only end devices attached and intended never to be used to connect to another switch? (Choose two.) bridge ID edge port extended system ID PortFast PVST+
-edge port -PortFast
A switch is configured to run STP. What term describes a field used to specify a VLAN ID? extended system ID port ID MAC Address bridge priority
-extended system ID
A switch is configured to run STP. What term describes a field used to specify a VLAN ID? extended system ID port ID bridge priority bridge ID
-extended system ID
Which three components are combined to form a bridge ID? extended system ID cost IP address bridge priority MAC address port ID
-extended system ID -bridge priority -MAC address
What are the benefits of EtherChannel technology?
-fault tolerance -load sharing -increased bandwidth -link redundancy
In which two PVST+ port states are MAC addresses learned? (Choose two.) forwarding disabled learning listening blocking
-forwarding -learning
In which two port states does a switch learn MAC addresses and process BPDUs in a PVST network? (Choose two.) blocking disabled forwarding learning listening
-forwarding -learning
What is the function of STP in a scalable network? It decreases the size of the failure domain to contain the impact of failures. It protects the edge of the enterprise network from malicious activity. It disables redundant paths to eliminate Layer 2 loops. It combines multiple switch trunk links to act as one logical link for increased bandwidth
-it disables redundant paths to eliminate layer 2 loops
Which two network design features require Spanning Tree Protocol (STP) to ensure correct network operation? (Choose two.) static default routes implementing VLANs to contain broadcasts redundant links between Layer 2 switches link-state dynamic routing that provides redundant routes removing single points of failure with multiple Layer 2 switches
-redundant links between layer 2 switches -removing single points of failure with mulitiple Layer 2 switches
A switch is configured to run STP. What term describes the reference point for all path calculations? root bridge root port designated port disabled
-root bridge
A switch is configured to run STP. What term describes the switch port closest, in terms of overall cost, to the root bridge? root port designated port alternate port disabled
-root port
Which port role is assigned to the switch port that has the lowest cost to reach the root bridge? root port non-designated port designated port disabled port
-root port
What are two load-balancing methods in the EtherChannel technology? (Choose two.) combination of source port and IP to destination port and IP source IP to destination IP source port to destination port combination of source MAC and IP to destination MAC and IP source MAC to destination MAC
-source IP to destination IP -source MAC to destination MAC
Which two parameters must match on the ports of two switches to create a PAgP EtherChannel between the switches? (Choose two.) MAC address speed VLAN information PAgP mode port ID
-speed -VLAN information
What is a requirement to configure a trunking EtherChannel between two switches? The participating interfaces must be physically contiguous on a switch. The allowed range of VLANs must be the same on both switches. The participating interfaces must be on the same module on a switch. The participating interfaces must be assigned the same VLAN number on both switches
-the allowed range of VLAs must be the same on both switches
Refer to the exhibit. Which switch will be the root bridge after the election process is complete?
S2, because the MAC address is the lowest, all of the other priority IDs matched
