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 IST Master is the regional root bridge for MST instance 0, and it serves as the point of connection between the region and the rest of the CIST.

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

MSTP reduces CPU and memory overhead by mapping many VLANs to a single instance, whereas Rapid PVST+ runs one STP process per VLAN.

Question 3

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

Accepted Answer

Max Age

Answer

Max Age (default 20 seconds) is the maximum time a switch retains BPDU information; if no BPDU is received within this period, the stored info is discarded.

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 spanning-tree vlan <id>' displays the STP mode, root bridge ID, port roles, and port states for the specified VLAN.

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

A bridge priority of 0 (or any lower value) makes the switch highly preferred as root bridge, as the lowest bridge ID wins the election.

(STP) Spanning Tree Protocol Practice Test

(STP) Spanning Tree Protocol Practice Test

STP Advanced Features and Variants 5