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Question 1 What effect does the global configuration command spanning-tree portfast

bpdufilter default have when enabled on an access switch?
All PortFast enabled ports become designated ports.
All PortFast enabled ports stop sending BPDUs, but if a BPDU is received on the port, the
port gets out of the PortFast state, thereby disabling the BPDU filtering.
All PortFast enabled ports start participating in the spanning-tree calculations.
All switch ports start filtering the superior BPDUs coming from other switches and the
access switch becomes a root bridge.
Question 2 What are three important steps in troubleshooting STP problems? (Choose three.)
Capture traffic on a saturated link and check whether identical frames are traversing
multiple links.
Check each side of a point-to-point link for duplex mismatch.
Adjust BPDU timers so that there is less overhead traffic on the switching fabric.
Administratively disable ports that should be blocking and check to see if connectivity is
restored.
Administratively disable multicasting and check to see if connectivity is restored.
Administratively create bridge loops and see what path the traffic takes.
Question 3 Which STP timer defines the length of time spent in the listening and learning
states?
hello time
forward aging
forward delay
max age
max delay
Question 4 What priority value should be entered on a switch, via the spanning-tree vlan 20
priority priority command, if the desired priority for VLAN 20 is 4116?
4116
4106
4096
32788

1Q (CST) Cisco PVST+ IEEE 802. Each switch determines a designated port that provides the best path to the root switch. However.1s (MST) Question 8 Which three parameters should match all switches within an MST region? (Choose three. the STP algorithm is run on all switches that have a root port.) configuration name VLAN-to-instance mappings revision number bridge priority port costs on trunk ports . A topology change will cause the switch where the change occurred to send messages about the change throughout the tree. Question 7 Which protocol should an administrator recommend to manage bridged links when the customer requires a fully redundant network that can utilize load balancing technologies and reconverge on link failures in less than a second? IEEE 802. The designated port will be on the switch with the best path to the root switch. Which STP feature should be implemented to prevent inadvertent loops in the network? PortFast BPDU filtering UDLD BPDU guard Question 6 Which statement is true about the Spanning Tree Protocol (STP)? With each network change.Question 5 Refer to the exhibit.1D(STP) IEEE 802. Switch SW1 is receiving traffic from SW2. SW2 is not receiving traffic from SW1.

what effect does the command spanning-tree mst 10 root primary have when entered on a single switch? sets the bridge priority on the switch to 24582 for MST instance 10 sets the bridge priority on the switch to 24576 for MST instance 10 sets the bridge priority on the switch to 28672 for MST instance 10 sets the bridge priority on the switch to 24586 for MST instance 10 Question 10 Which protocol extends the IEEE 802.1w is enabled on VLAN 1. PortFast is enabled on interface Fa0/6. . IEEE 802.trunk encapsulation method Question 9 Assuming that all switches in a network have the default bridge priority for each MST instance.1w Rapid Spanning Tree (RST) algorithm to multiple spanning trees? CST STP RSTP+ MST Question 11 Refer to the exhibit. What conclusion does the output support? Standard IEEE 802. The forward delay timer has been changed from the default value.1D behavior is shown.

The PVRST+ switch forwards 802. how many VLANs will be assigned to the default instance? 4064 4094 4062 4061 Question 13 Which interfaces should loop guard be enabled on? designated ports root port and alternate ports root port and ports configured with PortFast root ports ports configured with PortFast Question 14 One switch in a Layer 2 switched spanning-tree domain is converted to PVRST+ using the spanning-tree mode rapid-pvst global configuration mode command. but does not participate as a node in any spanning tree. After the sequence of commands is entered. The remaining switches are running PVST+.1D spanning tree for all VLANs. What is the effect on the spanning-tree operation? Spanning tree is effectively disabled in the network. .1D BPDUs.Question 12 Refer to the exhibit. All switches default to one 802. The PVSRT+ reverts to PVST+ to interoperate with the PVST+ switches.

Interfaces Fa0/1 through Fa0/6 are trunk ports. .1D IEEE 802. What two conclusions does the output show to be true? (Choose two. DLS1 is running IEEE 802.Question 15 Refer to the exhibit.1s on instance 1. Interface Fa0/12 will move into the errdisable state if a BPDU is received.) DLS1 is running IEEE 802.1D on instance 1. What implementation of spanning tree best describes the spanning-tree operational mode of the switch? PVRST+ IEEE 802.1s IEEE 802. DLS1 is the root bridge for instance 1.w Question 16 Refer to the exhibit.

Question 17 Refer to the exhibit.) Root guard is enabled on a per-port basis.Disabling 2/1 What is the cause of the problem? The STP PortFast BPDU Guard feature has disabled port 2/1 on the switch. Root guard should be configured on all ports on the desired root bridge to prevent another bridge from becoming the root. STP PortFast feature has been enabled on port 2/1. PAgP has removed port 2/1 from the EtherChannel bundle. At the same time. Root guard requires that PortFast be enabled on a switch port. STP is configured on all switches in the network. Question 18 Which two statements are true about STP root guard? (Choose two. STP PortFast feature has been disabled on port 2/1. the user on workstation A lost connectivity to the rest of the network. the port transitions to the blocking state to prevent a root bridge election. If a root guard enabled port receives a inferior BPDU from a nonroot switch. Recently. . the administrator received the console message: %SPANTREE-2-RX_PORTFAST:Received BPDU on PortFast enable port. Root guard re-enables a switch port once it stops receiving superior BPDUs.

Spanning tree will keep re-calculating. The port on switch B that connects to switch A is full duplex. The switch uses the max-age timer to age out entries in the MAC address table. Question 20 Users complain that they lost connectivity to all resources in the network. Ensure that the root guard and loop guard are properly configured on all distribution links. Question 21 What happens when a switch running IEEE 802.Question 19 Refer to the exhibit. The port on switch A that connects to switch B is half duplex. Switch A is performing carrier sense and collision detection. Check the port utilization on devices and look for abnormal values. Switch B will become the root switch. and switch B is not. The switch uses the hello to age out entries in the MAC address table. thereby consuming all the CPU normally used for traffic. thereby creating a loop. STP is enabled on all switches in the network. A network administrator suspects the presence of a bridging loop as a root cause of the problem.) Switch B may unblock its port to switch C. What are three problems that this scenario could create? (Choose three. Which two actions will determine the existence of the bridging loop? (Choose two.) Capture the traffic on the saturated link and verify if duplicate packets are seen. The switch uses the forward delay and the max-age timer to age out entries in the MAC address table.1D receives a topology change message from the root bridge? The switch uses the forward delay timer to age out entries in the MAC address table. . Autonegotiation results in both switch A and switch B failing to perform carrier sense. Verify that the management VLAN is properly configured on all root bridges. BPDUs may not successfully negotiate port states on the link between switch A and switch B. Confirm MAC port security is enabled on all access switches.

BackboneFast must be configured on all root switches. The port will transition to forwarding state automatically. The port will transition to the appropriate state as determined by the normal function of the spanning tree. Switches must be connected by a point-to-point link.Question 22 What three fields are included in a BPDU? (Choose three. UplinkFast must be configured on all designated switches.) cost of path link-state ID port ID bridge ID STP ID Question 23 What will happen when a BPDU is received on a loop guard port that is in a loopinconsistent state? The port will transition to blocking state. The port will be disabled and the administrator must re-enable it manually. .) All ports that are directly connected to end stations must be enabled as designated ports. Question 24 Which two statements are true about the RSTP negotiations between switches? (Choose two. It greatly improves the restoration times for any VLAN that requires a topology convergence due to link up.

What was done on the switch? The command spanning-tree portfast bpduguard default was issued in interface configuration mode. The command spanning-tree portfast bpduguard default was issued in global configuration mode. The command no spanning-tree uplinkfast was issued in global configuration mode. The command spanning-tree etherchannel guard misconfig was issued in interface configuration mode.Question 25 Refer to the exhibit. The command no spanning-tree backbonefast was issued in global configuration mode. The command spanning-tree etherchannel guard misconfig was issued in global configuration mode. The configuration on the switch was changed between Output #1 and Output #2. .