WAN Redundancy

Correct Answer: Incorrect failover configuration

The most likely cause of the given network issue is the 'Incorrect failover configuration'. When a primary WAN link fails, the network should automatically switch over to the backup link. If the backup link isn't being utilized, it suggests that the failover configuration, which is responsible for this automatic switch, is not correctly configured. On the other hand, 'Outdated router firmware' is less likely to be the immediate cause of this problem because it would typically cause more widespread connectivity issues. 'Mismatched MTU settings' could potentially cause issues with data transmission but wouldn't entirely stop the backup link from being used. Finally, 'Bandwidth limitations' refer to the maximum data transfer rate of a network, and while this could lead to slow speeds, it wouldn't cause the backup link to remain unused.

Correct Answer: Reprovision one of the office backup links to be the primary link for the new location

When consolidating two branch offices into one, maintaining optimal WAN redundancy should be done by reprovisioning one of the office backup links to be the primary link for the new location. This way, both offices can continue their business operations uninterrupted even in case of a primary link failure. The other proposed decisions may lead to business disruptions or network inefficiencies. Disconnecting both backup links would remove fail-safe options. Increasing the primary link's bandwidth may incur unneeded cost and may not improve redundancy. Combining the two backup links into one doesn't ensure optimal load balancing and redundancy as it reduces failure isolation.

Correct Answer: Implement multiple carriers and load balancing

Implementing multiple carriers and load balancing would provide the best reliability of a company's WAN connections. Establishing connections with multiple ISPs (Internet Service Providers) multiplies the available paths for data transfer, thus achieving redundancy. This redundancy is essential for maintaining connectivity even if one ISP experiences problems. Additionally, load balancing is a technique to distribute network traffic efficiently across multiple paths in the network to optimize responsiveness and avoid overload of any single path. 'Increase primary link bandwidth' would be an incorrect answer because although it might help improve speed, it does not necessarily increase the reliability or resilience of the connections in the face of potential failures. 'Configure static routes' is also not the correct answer as it doesn't provide redundancy or control of traffic balancing which are critical for reliability. Static routes are manually configured and don't automatically adjust to changes in the network layout. 'Upgrade router hardware' might improve the performance or capacity, but does not inherently increase the reliability of the WAN connections. Router hardware can still fail, regardless of how new or updated it is.