Refer To The Exhibit. A Forwarding Loop Has Been Created

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Refer to the exhibit. A forwarding loop has been created between switches A, B, and D. Given the out generated by the show spanning-tree vlan command on switch B and D, what could be the cause of t problem? The switches on the network have not been configured with the same STP instance. The switches on the network have not agreed on the common STP root. The link between switches A and B has not been configured as a trunk. The link between switches A and B has not been configured as an EtherChannel. 2

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Which statement is true about UDLD? It is automatically enabled. It allows devices to transmit traffic one way. It allows a switch to detect a unidirectional link and shut down the affected interface. It will disable an EtherChannel bundle if one link has failed.

Refer to the exhibit. Given the output generated by the show spanning-tree mst configuration comm which two statements are true? (Choose two.) The switch has automatically incremented the MST revision number to 11. The MST region name was configured with the name CAMPUS1 global configuration command The switch requires the spanning-tree mode mst global configuration command to enable MST. The switch was configured with the spanning-tree mst 1 root primary MST configuration comm VLANs 1 through 10 have been configured with the instance 1 vlan 1-10 MST configuration com 4

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Which two STP features will protect the network against forwarding loops? (Choose two.) PortFast UplinkFast BackboneFast Loop Guard Unidirectional Link Detection (UDLD) Which two statements are true about the RSTP negotiations between switches? (Choose two.) UplinkFast must be configured on all designated switches. BackboneFast must be configured on all root switches. Switches must be connected by a point-to-point link. All ports that are directly connected to end stations must be enabled as designated ports. All ports connected to end stations must be configured as edge ports.

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Refer to the exhibit. Given the information in the exhibit, which Cisco feature has been configured on interface? UDLD Loop Guard PortFast BackboneFast 7

Which two benefits are provided by MST as it is used with RSTP? (Choose two.) load balancing multiple spanning trees with ISL trunking rapid router redundancy rapid ISL convergnece subsecond reconvergence What are three important steps in troubleshooting STP problems? (Choose three.)

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Administratively disable multicasting and check to see if connectivity is restored. Administratively create bridge loops and see what path the traffic takes. Administratively disable ports that should be blocking and check to see if connectivity is restored. Check each side of a point-to-point link for duplex mismatch. Capture traffic on a saturated link and check whether identical frames are traversing multiple links Adjust BPDU timers so that there is less overhead traffic on the switching fabric.

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Which statement is true regarding a port configured with Loop Guard? Once a BPDU is received on a Loop Guard port that is in a loop-inconsistent state, the port will t to forwarding state automatically. Once a BPDU is received on a Loop Guard port that is in a loop-inconsistent state, the port will t to the appropriate state as determined by the normal function of Spanning Tree. Once a BPDU is received on a Loop Guard port that is in a loop-inconsistent state, the port will b disabled and the administrator must re-enable it manually. Once a BPDU is received on a Loop Guard port that is in a loop-inconsistent state, the port will t to blocking state.

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1 Which three statements regarding RSTP edge ports are true? (Choose three.) Edge ports can have another switch connected to them as long as the link is operating in full dup Edge ports function similarly to UplinkFast ports. Edge ports immediately transition to learning mode and then forwarding mode when enabled. Edge ports never generate topology changes notifications (TCNs) when the port transitions to a d enabled status. Edge ports should never connect to another switch. If an edge port receives a BPDU, it becomes a normal spanning-tree port.

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Refer to the exhibit. STP is configured on all switches in the network. Recently, the user on Worksta connectivity to the rest of the network. At the same time, the administrator received the console mess 2005 May 12 15:13:32 %SPANTREE-2-RX_PORTFAST:Received BPDU on PortFast enable port. Disabling 2/1 2005 May 12 15:13:32 %PAGP-5-PORTFROMSTP:Port 2/1 left bridge port 2/1

What is the cause of the problem? STP PortFast feature has been disabled on port 2/1. STP PortFast feature has been enabled on port 2/1. The STP PortFast BPDU Guard feature has disabled port 2/1 on the switch. PAgP has removed port 2/1 from the EtherChannel bundle. 2

1 Which interfaces should Loop Guard be enabled on? root ports designated ports root port and alternate ports ports configured with PortFast root port and ports configured with PortFast

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Which protocol should an administrator recommend to manage bridged links when the customer requ fully redundant network that can utilize load balancing technologies and reconverge on link failures i than a second? IEEE 802.1Q (CST) IEEE 802.1s (MST) Cisco PVST+ IEEE 802.1D(STP) 1

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Refer to the exhibit. Switch A is the root switch. The port on Switch A that connects to Switch B is h duplex. The port on Switch B that connects to Switch A is full duplex. What are three problems that scenario could create? (Choose three.) Switch A is performing carrier sense and collision detection, while Switch B is not. Autonegotiation results in both Switch A and Switch B failing to perform carrier sense. Switch B will become the root switch. BPDUs may not successfully negotiate the link between Switch A and Switch B. Switch B may unblock its port to Switch C, thereby creating a loop.

Spanning-tree will keep re-calculating, consuming all the CPU normally used for traffic. 15

Refer to the exhibit. RSTP has been configured on this network. Given the information in the exhibit, w statement is true? The link between Access1 and Hub1 is a point-to-point link operating in full-duplex mode. The link between Access2 and Access4 is a shared link operating in half-duplex mode. The link between Access4 and PC2 is a point-to-point link operating in full-duplex mode. The link between Dist1 and the Access1 is a shared link operating in full-duplex mode. The link between Dist1 and the Server is a shared link operating in half-duplex mode. 16 Which protocol extends the IEEE 802.1w Rapid Spanning Tree (RST) algorithm to multiple spanningPVST+ PVST IEEE 802.1q (CST) IEEE 802.1s (MST) 1 Which three statements regarding RSTP are true? (Choose three.) 7 An RSTP BPDU carries information about port roles and is sent to neighbor switches only. RSTP elects a root bridge in exactly the same way as 802.1D. RSTP is capable of reverting back to 802.1D while still maintaining the benefits of 802.1w. RSTP is recognized as the IEEE 802.1w standard. There are only three RSTP port states: discarding, listening, and forwarding. UplinkFast and BackboneFast are compatible with RSTP.