Quiz : CCNA Lan Chapter #4

The provided command output shows that the VTP domain name on SW1 is "CCNA" while on SW2 it is "CCNP". This difference in VTP domain names is causing the switches to fail to exchange VLAN information. To correct the problem, both switches must be configured with the same VTP domain name, which means SW2 needs to be configured with the VTP domain name "CCNA".

The output provided verifies that VTP advertisements are being exchanged. This can be inferred from the fact that the output displays information about VTP advertisements, such as the number of advertisements received and the status of the VTP domain. The other options can be ruled out because there is no mention of verifying the VTP password, VTP version, or VTP domain name.

Two possible explanations for Switch1 not participating in the VTP management process with the other switches could be that Switch1 is in a different management domain and that Switch1 is using VTP version 1 while Switch2 is using VTP version 2.

VTP (VLAN Trunking Protocol) is a Cisco proprietary protocol that allows for the dynamic propagation of VLAN information across a switched network. When VTP is configured on a switched network that incorporates VLANs, it enables switches in the same VTP domain to automatically synchronize and update their VLAN configuration. This means that when a VLAN change is made on one switch, it is communicated to all switches in the same VTP domain, reducing the need for manual configuration on each individual switch. Therefore, the statement "VTP dynamically communicates VLAN changes to all switches in the same VTP domain" is true.

In this scenario, Switch SW1 is configured as a VTP server, Switch SW2 and SW4 are configured as VTP clients, and Switch SW3 is configured in VTP transparent mode. VTP updates are only sent by VTP servers and received by VTP clients. Since SW2 is a VTP client, it receives the updates from SW1. However, SW3 is in transparent mode, so it does not receive any VTP updates. SW4 is also a VTP client and receives the updates from SW1. However, only SW4 synchronizes the VLAN information based on those updates. Therefore, the correct answer is that SW3 and SW4 receive updates, but only switch SW4 synchronizes VLAN information.

The first statement is true because VTP messages are only sent over trunk links. The second statement is true because the VTP domain name is case sensitive, meaning that "VLAN" and "vlan" would be considered different domain names.

To participate in the same VTP domain, three parameters must be identical on all switches: domain name, domain password, and version number. The domain name is used to identify the VTP domain, and all switches within the domain must have the same name. The domain password is used for authentication purposes, and again, all switches must have the same password to participate in the domain. The version number represents the VTP version being used, and all switches must have the same version number to ensure compatibility and proper communication within the domain.

In VTP client mode operation, the switch is unable to add VLANs to the network. This means that it cannot create or modify VLANs. However, it can still forward VLAN information to other switches in the same VTP domain. This allows the client switch to receive and update its VLAN database based on the information received from the VTP server. This feature ensures that the client switch stays synchronized with the VLAN configuration of the network.

The reason why the new VLAN added to Switch3 does not show up on the other switches is that VLANs created on transparent mode switches are not included in VTP advertisements. In transparent mode, the switch does not participate in VTP updates and does not forward VTP advertisements to other switches. Therefore, any VLANs created on a transparent mode switch will not be advertised to other switches in the VTP domain.

A VTP configured switch issues a summary advertisement when a five-minute update timer has elapsed. This timer is responsible for periodically updating the VTP information across the network. When the timer expires, the switch sends out a summary advertisement to inform other switches in the VTP domain about any changes or updates that have occurred. This helps to ensure that all switches have the most up-to-date information and can synchronize their VLAN configurations.

When the cable is disconnected from F0/1 on S2, it will not have access to the VTP updates from the VTP server (S1). However, S2 will retain the VLANs as of the latest known revision, meaning it will still have the VLAN information that it received before the cable was disconnected. However, if S2 is reloaded or restarted, it will lose the VLAN information because it won't be able to synchronize with the VTP server.

In VTP transparent mode, switches can add VLANs of local significance only, meaning they can create and modify VLANs on their own switch. They also pass any VLAN management information that they receive to other switches, allowing them to communicate and synchronize VLAN information with other switches in the network.

VTP messages are sent between switches in a domain using Layer 2 multicast. Multicasting allows a single packet to be sent to multiple recipients simultaneously, reducing network traffic. In the case of VTP messages, they are sent to a specific multicast address, which ensures that only switches in the same VTP domain receive and process the messages. This helps in synchronizing VLAN information across the switches in the domain.

To avoid incorrect VLAN information from propagating through the network when replacing a failed switch, the administrator should change the VTP domain name on the replacement switch. This is because VTP (VLAN Trunking Protocol) is used to synchronize VLAN information across switches in a domain. By changing the VTP domain name, the replacement switch will not receive or propagate any VLAN information from the previous switch, preventing any potential issues caused by incorrect VLAN information.

The default propagation of VLANs on a trunked link is to include all VLANs. This means that all VLAN traffic will be allowed to pass through the trunked link by default.

VTP pruning is a feature that allows switches to dynamically remove unnecessary VLAN traffic from trunk links. It helps to optimize bandwidth utilization by preventing the flooding of broadcast traffic across trunks. Therefore, the statement "Pruning will prevent unnecessary flooding of broadcasts across trunks" is true. Additionally, VTP pruning can only be configured on VTP servers, as they are responsible for managing VLAN information in the domain. Hence, the statement "Pruning can only be configured on VTP servers" is also true.

The problem is caused by the mismatch in the VTP revision number between the lab and production networks. By re-entering all appropriate VLANs, except VLAN 1, manually on Switch1, the VLAN information will be updated with the correct revision number and propagate throughout the network, resolving the connectivity issue.

When a client mode switch in a VTP management domain receives a summary advertisement with a revision number higher than its current revision number, it issues an advertisement request for new VLAN information. This means that the switch is requesting the updated VLAN information from the VTP server in order to synchronize its VLAN database with the latest changes.

When the new switch SW2 with a default configuration and revision number of 0 is inserted in the existing VTP domain Lab_Network, it will operate as a VTP server. However, since its revision number is 0, it will not impact the existing VLAN configuration in the domain. This means that the switch will not overwrite or delete any existing VLAN configurations in the network.

The output confirms that the switch is configured to advertise its VLAN configuration to other VTP-enabled switches in the same VTP domain. This can be inferred from the fact that the switch is displaying the VTP configuration revision number and the number of existing VLANs. Additionally, the output suggests that if this switch is added to an established network, the other VTP-enabled switches in the same VTP domain will consider their own VLAN information to be more recent than the VLAN information advertised by this switch. This can be deduced from the fact that the VTP configuration revision number of this switch is lower than the revision numbers of the neighboring devices.