READ Free Dumps For Cisco- 400-101
| Question ID 18598 | Refer to the exhibit.
While troubleshooting high CPU utilization on one of your Cisco Catalyst switches, you find
that the issue is due to excessive flooding that is caused by STP. What can you do to
prevent this issue from happening again?
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| Option A | Disable STP completely on the switch.
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| Option B | Change the STP version to RSTP.
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| Option C | Configure PortFast on port-channel 1.
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| Option D | Configure UplinkFast on the switch.
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| Option E | Configure PortFast on interface Gi0/15.
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| Correct Answer | E |
Explanation Explanation: Topology Changes (TC) should be a rare event in a well-configured network. When a link on a switch port goes up or down, there is eventually a TC, once the STP state of the port is changing to or from forwarding. When the port is flapping, this would cause repetitive TCs and flooding. Ports with the STP portfast feature enabled will not cause TCs when going to or from the forwarding state. The configuration of portfast on all end-device ports (such as printers, PCs, and servers) should limit TCs to a low amount and is highly recommended. Reference: http://www.cisco.com/c/en/us/support/docs/lan-switching/spanning-tree- protocol/28943-170.html
| Question ID 18599 | Which two statements are true about RSTP? (Choose two.)
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| Option A | By default, RTSP uses a separate TCN BPDU when interoperating with 802.1D switches.
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| Option B | By default, RTSP does not use a separate TCN BPDU when interoperating with 802.1D switches.
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| Option C | If a designated port receives an inferior BPDU, it immediately triggers a reconfiguration.
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| Option D | By default, RTSP uses the topology change TC flag.
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| Option E | If a port receives a superior BPDU, it immediately replies with its own information, and no reconfiguration is triggered.
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| Correct Answer | B,D |
Explanation Explanation: The RSTP does not have a separate topology change notification (TCN) BPDU. It uses the topology change (TC) flag to show the topology changes. Reference: http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2950/software/release/12- 1_9_ea1/configuration/guide/scg/swmstp.html