CCENT/CCNA Icnd2 Fun Quiz

PortFast is a feature in STP (Spanning Tree Protocol) that allows an interface to immediately transition to the Forwarding State as soon as it becomes physically active. This feature is used to bypass the usual STP listening and learning states, which can cause delays in network connectivity. By enabling PortFast, the interface can start forwarding traffic without waiting for the usual STP convergence process, making it ideal for interfaces connected to end devices such as computers or printers.

The smallest numeric bridge ID wins the election.

The default VTP setting of VTP server mode means that the switch can configure VLANs, so the VLAN is configured. However, being in server mode, the configuration commands only show up in the show vlan brief command output, and are not listed as part of the running-config file.

802.1Q is the correct answer because it is a protocol used for trunking in Ethernet networks. It adds a 4-byte header to the Ethernet frame, which includes information about the VLAN the frame belongs to. This allows multiple VLANs to be carried over a single trunk link. Unlike ISL, which adds a header for all VLANs, 802.1Q allows for the exclusion of specific VLANs, making it the appropriate choice for adding the trunking header for all VLANs except one.

Cisco switches use the extended system ID format for bridge IDs by default, in which the priority field is broken down into a base priority value (32,768 in this case)plus the VLAN ID. The priority of this switch allows it to be capable of being the root switch, but the command output does not supply enough information to know whether this switch is currently root.

ISL (Inter-Switch Link) is the correct answer because it fully encapsulates the original Ethernet frame in a trunking header rather than inserting another header inside the original Ethernet header. ISL is a Cisco proprietary protocol used for VLAN trunking, allowing multiple VLANs to be carried over a single link between switches. It adds a 26-byte header to the original Ethernet frame, including VLAN information, and then encapsulates the entire frame in a new Ethernet frame. This allows the VLAN information to be preserved as the frame is forwarded between switches.

Listening and Learning are transitory port states, used only when moving from the Blocking to the Forwarding State. Discarding is not an 802.1d STP port state.

Listening and Learning are transitory port states, used only when moving from the Blocking to the Forwarding state. Discarding is not an 802.1d STP port state. Forwarding and Blocking are stable states.

The VTP modes that allow VLANs to be configured on a switch are Server and Transparent. In Server mode, the switch can create, modify, and delete VLANs, and these changes are propagated to other switches in the VTP domain. In Transparent mode, the switch can create, modify, and delete VLANs, but these changes are not propagated to other switches. The other VTP modes, Client and Dynamic, do not allow VLAN configuration on the switch.

Nonroot switches forward Hellos received from the root; the root sends these Hellos based on the root’s configured Hello timer.

VTP does not require a password, although if a password is used, the password must match. VTP sends VTP updates immediately after a VLAN database change. However, VTP only sends VTP messages over trunks, and 2960s default to using a trunking administrative mode of auto, which does not initiate the trunking negotiation process. So, none of the switches automatically form a trunk, and no VTP messages are sent.

The two interfaces default to a port cost of 19 (Fa0/13) and 4 (Gi0/1), making SW3’s cost to reach the root 10 + 19 = 29 out Fa0/13, and 20 + 4 = 24 over Gi0/1. SW3 therefore chooses Gi0/1 as its root port. SW3 could then advertise a cost of 24 (cost to reach the root) Hello out Fa0/13, but it would be inferior to the Hello already being
received on Fa0/13 (cost 10), so SW3 would not choose Fa0/13 as a designated port.

The auto setting means that the switch can negotiate trunking, but it can only respond to negotiation messages, and it cannot initiate the negotiation process. So, the other switch must be configured to trunk or to initiate the negotiation process (based on being configured with the dynamic desirable option.)

The command "spanning-tree vlan vlan-number root {primary | secondary}" changes the value of the bridge ID by specifying whether the switch should be the primary or secondary root bridge for the specified VLAN. The command "spanning-tree vlan vlan-number priority value" also changes the value of the bridge ID by setting the priority value for the specified VLAN.

The IEEE 802.1w standard, called Rapid STP, provides much faster STP convergence.

The command "show interfaces gi0/1 switchport" lists the operational state of interface Gigabit 0/1 in regard to VLAN trunking. This command specifically displays the switchport configuration and status information for the specified interface. On the other hand, the command "show interfaces gi0/1 trunk" is not applicable in this context as it displays information about trunk interfaces and their associated VLANs.

The domain name and password must be equal, and the switches must connect using a trunk before VTP will work. It is normal to have some switches as servers and some as clients. A mismatched pruning configuration setting does not prevent the synchronization of VLAN databases.

RSTP uses port states of Forwarding, Learning, and Discarding, with Forwarding and Learning States performing the same basic functions as the STP port states with the same name.