CCNA Day 21- STP Part 2

What are the two 'stable' STP port states?

Blocking, Forwarding

What are the two 'transitional' STP port states?

Listening, Learning

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

Blocking

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

No

STP: Do interfaces in a blocking state send BPDUs?

No

STP: Do interfaces in a blocking state receive BPDUs?

Yes

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

No

STP default Forward delay timer:

15 seconds

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

No

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

Yes

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

No

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

No

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

Yes

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

Yes

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

Yes

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

Yes

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

Yes

STP default hello timer:

2 seconds

STP default max age timer:

20 seconds (10*hello timer)

STP BPDUs are only forwarded on [...] ports.

designated

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

can

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

can't

PVST+ BPDUs are sent to destination MAC address:

0100.0ccc.cccd

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

0180.c200.0000

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

root bridge

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

Portfast

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

BPDU Guard

Enable portfast on a switch port:

SW1(config-if)# [...]

spanning-tree portfast

Enable portfast on all access ports on the switch:

SW1(config)# [...]

spanning-tree portfast default

SW1(config)# spanning-tree portfast default

This command enables portfast on which ports?

All access ports

Enable BPDU Guard on a switch port:

SW1(config-if)# [...]

spanning-tree bpduguard enable

Enable BPDU Guard on all Portfast-enabled interfaces:

SW1(config)# [...]

spanning-tree portfast bpduguard default

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

Root Guard

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

Loop Guard

Configure spanning tree in PVST mode:

SW1(config)# [...]

spanning-tree mode pvst

Configure the spanning-tree root for a VLAN:

SW1(config)# [...]

spanning-tree vlan vlan-id root primary

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

24576

Configure the spanning-tree secondary root for a VLAN:

SW1(config)# [...]

spanning-tree vlan vlan-id root secondary

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

28672

Configure the STP cost of an interface:

SW1(config-if)# [...]

spanning-tree vlan vlan-id cost cost

Configure the STP priority of an interface:

SW1(config-if)# [...]

spanning-tree vlan vlan-id port-priority priority