EXIN CDCP Exam Questions & Answers

Correct Answer: C

The current recommended temperature for ICT equipment as described in the ASHRAE TC 9.9 guideline is 18-27 C (64.4 - 80.6). This is the recommended range for the dry-bulb temperature at the inlet of the servers, which is the most critical parameter for ensuring the optimal performance and reliability of the ICT equipment. The recommended range is based on the thermal specifications of the majority of the ICT equipment in the market, as well as the energy efficiency and environmental considerations of the data centre cooling systems. The recommended range is suitable for Classes A1 to A4 of the ASHRAE thermal guideline classes, which cover different types and generations of ICT equipment.

Correct Answer: C

Data centres are essential for supporting the IT operations and applications of various businesses across different industries. Data centre downtime can have a negative impact on the business results, such as loss of revenue, customer satisfaction, productivity, reputation, and competitive advantage. According to a web search, the average cost of data centre downtime in 2020 was $8,851 per minute, and the average duration of a data centre outage was 95 minutes1. This means that a typical data centre outage could cost a business over $840,000 in direct and indirect losses1. Therefore, data centre downtime can have a significant impact on the business results, regardless of the industry or sector.

Correct Answer: A

Glass door racks are a type of rack that have solid glass front doors and rear door heat exchangers (RDHx). RDHx are devices that use facility coolant to absorb heat from the exhaust air of the IT equipment and return cool air to the room. RDHx can be either passive or active, depending on the fan configuration. In general, IT hardware within the rack is air-cooled and the door heat exchanger uses facility coolant to absorb heat from exhaust air to return air to the facility at or near inlet air temperature to the rack. This rear door heat exchanger can either be a passive or active solution. When dealing with glass door racks, cool air is injected into the rack from the rear door in a downflow direction. This means that the cool air flows from the top to the bottom of the rack, following the natural convection of the hot air rising. This way, the cool air can reach all the IT equipment in the rack and prevent hot spots or overheating.