STP Advanced Features and Variants 5

Question 1

What is the role of the IST Master in MSTP?

Accepted Answer

The switch within an MST region with the lowest bridge ID for instance 0, acting as the root for the IST

Answer

The switch responsible for sending BPDUs to all other MST regions

Answer

The switch that manages VLAN-to-instance mapping updates

Answer

The backup root bridge for all MST instances simultaneously

Question 2

When comparing Rapid PVST+ to MSTP, which statement is accurate?

Accepted Answer

MSTP is more scalable because it groups VLANs into instances, reducing the number of spanning tree calculations

Answer

Rapid PVST+ scales better in large VLAN environments because it uses fewer BPDUs

Answer

Rapid PVST+ and MSTP produce identical BPDU counts regardless of VLAN count

Answer

MSTP cannot interoperate with Rapid PVST+ under any configuration

Question 3

Which STP timer determines how long a switch stores BPDU information before considering the root bridge unreachable?

Accepted Answer

Max Age

Answer

Hello Time

Answer

Forward Delay

Answer

Hold Time

Question 4

In a Cisco network, which command verifies the current STP mode and root bridge information for a specific VLAN?

Accepted Answer

show spanning-tree vlan <id>

Answer

show stp status vlan <id>

Answer

show bridge-group vlan <id>

Answer

show vlan spanning-tree detail <id>

Question 5

What is the purpose of configuring 'spanning-tree vlan <id> priority 0' on a switch?

Accepted Answer

Makes the switch the most preferred root bridge candidate for that VLAN

Answer

Disables STP entirely for that VLAN

Answer

Sets the switch as a non-root bridge that will never participate in elections

Answer

Configures the switch to use rapid convergence for that VLAN only

Question 6

Which feature automatically selects the optimal STP port priority and cost values based on the port speed in modern Cisco implementations?

Accepted Answer

STP Auto-cost based on interface bandwidth detection

Answer

Auto-negotiation of STP parameters via LLDP

Answer

Dynamic STP (dSTP) port calibration

Answer

Port cost is always manually configured; no automatic feature exists

Question 7

When two switches are connected by multiple parallel links and STP is running, what happens to the redundant links without additional configuration?

Accepted Answer

STP blocks all but one link to prevent loops, wasting bandwidth

Answer

All links forward traffic in round-robin fashion

Answer

Links are automatically aggregated into an EtherChannel

Answer

Each link is assigned to a different VLAN automatically