Explanation
A DR site is a backup site that can be used to restore business operations in case of a disaster that affects the primary site. A warm site is a DR site that has some equipment and data ready to be activated quickly, but not as fast as a hot site that has fully operational systems and data. A cold site is a DR site that has only basic infrastructure and no equipment or data. The location of a DR site is an important factor to consider when designing and implementing a DR plan. A DR site that is too close to the primary site may be affected by the same disaster, such as a power outage, a flood, or an earthquake. A DR site that is too far away from the primary site may incur higher costs and latency issues. Therefore, a good practice is to set up a DR site that is geographically located in another region that has different risk factors and environmental conditions than the primary site. This can help ensure that the DR site is available and accessible when needed. References:
https://www.comptia.org/training/resources/exam-objectives/comptia-server-sk0-005-exam-objectives (Objective 3.3)

A sniffer (also known as a packet analyzer) is a tool that captures and inspects data packets traveling across the network. In this case, using a sniffer would help identify suspicious or malicious redirection of traffic, possibly caused by a man-in-the-middle attack, DNS hijacking, or malware.
* Sniffer (Answer D): This tool will allow the senior administrator to inspect the network traffic and identify if and how requests to the anti-malware website are being intercepted or redirected.
* Data loss prevention (Option A): DLP tools focus on preventing data leakage rather than analyzing traffic redirection.
* File integrity monitor (Option B): This checks for unauthorized changes to files, which may not directly address network traffic redirection.
* Port scanner (Option C): A port scanner would only identify open ports on devices, which is unrelated to the redirection issue.
CompTIA Server+ Reference:This topic is addressed under SK0-005 Objective 4.2: Explain server roles and their purposes.

Push notifications are messages that are sent from an application or a service to a user's device without requiring the user to open or request them. They can be used as a cost-effective technique for implementing MFA (Multi-Factor Authentication) on servers by sending verification codes or approval requests to the user's smartphone or tablet when they try to log in to the server. Verified References: [Push notifications], [MFA]

Explanation
The first thing that the technician should do to return the server to service as soon as possible is downgrade the NIC firmware. Firmware is a type of software that controls the basic functions of hardware devices, such as network interface cards (NICs). Firmware updates can provide bug fixes, performance improvements, or new features for hardware devices. However, firmware updates can also cause compatibility issues, configuration errors, or functionality failures if they are not installed properly or if they are not compatible with the device model or driver version. Downgrading the firmware means reverting to an older version of firmware that was previously working fine on the device. Downgrading the firmware can help resolve any problems caused by a faulty firmware update and restore normal operation of the device.