18 - Spanning Tree Part 2

Question 1

[…] allows an STP port to move immediately to the forwarding state.

Answer 1

Portfast

Question 2

Configure spanning tree in PVST mode:
SW1(config)# […]

Answer 2

spanning-tree mode pvst

Question 3

Configure the spanning-tree root for a VLAN:
SW1(config)# […]

Answer 3

spanning-tree vlan <vlan-id> root primary</vlan-id>

Question 4

Configure the spanning-tree secondary root for a VLAN:
SW1(config)# […]

Answer 4

spanning-tree vlan <vlan-id> root secondary</vlan-id>

Question 5

Configure the STP cost of an interface:
SW1(config-if)# […]

Answer 5

spanning-tree vlan <vlan-id> cost <cost></cost></vlan-id>

Question 6

Configure the STP priority of an interface:
SW1(config-if)# […]

Answer 6

spanning-tree vlan <vlan-id> port-priority <priority></priority></vlan-id>

Question 7

Enable BPDU Guard on a switch port:
SW1(config-if)# […]

Answer 7

spanning-tree bpduguard enable

Question 8

Enable BPDU Guard on all Portfast-enabled interfaces:
SW1(config)# […]

Answer 8

spanning-tree portfast bpduguard default

Question 9

Enable portfast on a switch port:
SW1(config-if)# […]

Answer 9

spanning-tree portfast

Question 10

Enable portfast on all access ports on the switch:
SW1(config)# […]

Answer 10

spanning-tree portfast default

Question 11

If an interface with […] enabled receives a BPDU from another switch, the interface will be shut down.

Answer 11

BPDU Guard

Question 12

PVST+ BPDUs are sent to destination MAC address:

Answer 12

0100.0ccc.cccd

Question 13

spanning-tree vlan vlan-id root secondary sets the STP priority to […]

Answer 13

28672

Question 14

spanning-tree vlan vlan-id root primary sets the STP priority to […], or 4096 less than the current root’s priority.

Answer 14

24576

Question 15

Standard STP (NOT PVST) BPDUs are sent to destination MAC address:

Answer 15

0180.c200.0000

Question 16

STP BPDUs are only forwarded on […] ports.

Answer 16

designated

Question 17

STP default Forward delay timer:

Answer 17

15 seconds

Question 18

STP default hello timer:

Answer 18

2 seconds

Question 19

STP default max age timer:

Answer 19

20 seconds (10*hello timer)

Question 20

STP: A blocking interface [can/can’t] move directly to a forwarding state.

Answer 20

can’t

Question 21

STP: A forwarding interface [can/can’t] move directly to a blocking state.

Answer 21

can

Question 22

STP: Do interfaces in a blocking state learn MAC addresses?

Answer 22

No

Question 23

STP: Do interfaces in a blocking state receive BPDUs?

Answer 23

Yes

Question 24

STP: Do interfaces in a blocking state send BPDUs?

Answer 24

No

Question 25

STP: Do interfaces in a blocking state send/receive regular network traffic?

Answer 25

No

Question 26

STP: Do interfaces in a Forwarding state learn MAC addresses?

Answer 26

Yes

Question 27

STP: Do interfaces in a Forwarding state send/receive BPDUs?

Answer 27

Yes

Question 28

STP: Do interfaces in a Forwarding state send/receive regular network traffic?

Answer 28

Yes

Question 29

STP: Do interfaces in a Learning state learn MAC addresses?

Answer 29

Yes

Question 30

STP: Do interfaces in a Learning state send/receive BPDUs?

Answer 30

Yes

Question 31

STP: Do interfaces in a Learning state send/receive regular network traffic?

Answer 31

No

Question 32

STP: Do interfaces in a Listening state learn MAC addresses?

Answer 32

No

Question 33

STP: Do interfaces in a Listening state send/receive BPDUs?

Answer 33

Yes

Question 34

STP: Do interfaces in a Listening state send/receive regular network traffic?

Answer 34

No

Question 35

STP: Non-designated ports are in a [...] state.

Answer 35

Blocking

Question 36

SW1(config)# spanning-tree portfast default This command enables portfast on which ports?

Answer 36

All access ports

Question 37

The STP timers on the [...] determine the timers used for all switches in the network.

Answer 37

root bridge

Question 38

What are the two 'stable' STP port states?

Answer 38

Blocking, Forwarding

Question 39

What are the two 'transitional' STP port states?

Answer 39

Listening, Learning

Question 40

Which STP optional feature prevents a newly connected switch from becoming the root bridge?

Answer 40

Root Guard

Question 41

Which STP optional feature shuts down an interface if it stops receiving BPDUs?

Answer 41

Loop Guard