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Editor to share with you how the blade server heat dissipation, I believe that most people do not know much about it, so share this article for your reference, I hope you will learn a lot after reading this article, let's learn about it!

To apply a blade server, you must select one of the methods. This choice is based on the constraints of the current facility as well as the needs and preferences of users.

The choice of application method

After understanding the constraints of existing facilities and making an appropriate trade-off between the needs and preferences of users, you can choose from the five basic approaches described above. The choice of application method of blade server is based on the problem of heat dissipation, because these problems are the most important constraint factors in the actual system. After the mode of application is determined, the problem of power supply is also determined.

The most important uncertain factor affecting the application mode is the density of blade servers. Many users prefer to install blade servers at * density. This is often not an appropriate choice in existing data center environments. In fact, most blade servers have a modular rack structure and can be installed in cabinets with low density. For example, the IBM BladeCenter ™uses a separate rack, and one to six blades can be installed in a cabinet. Although reducing installation density does not seem to take full advantage of blade servers, the cost, availability, and installation speed of the system have actually increased, especially when blade servers are installed in existing data center environments.

Many current data centers are designed with power densities of even lower 2kW per cabinet. When installing blade servers at the power of each cabinet 10-30kW in such an environment, these blade servers consume a large amount of power and heat dissipation, which is out of proportion to the original design of the machine room. For this reason, there is usually no practical benefit in saving space when installing blade servers in an existing data center. Therefore, it is practical and cost-effective to distribute blade servers in existing data centers. Installing blade servers at saturated density is usually cost-effective in computer room facilities built specifically to support high-density solutions-extremely large installations or extremely small space.

Therefore, the core choice of blade server installation is the dispersion of blade server installation-that is, how many blades are installed in each cabinet. The brand and model of the blade server chosen by the user may restrict the dispersion of the blade. for example, some blade servers use a separate rack, which is easy to install separately. Other blade servers use a backplane system that makes decentralized installation impractical. For a more comprehensive and detailed discussion of this issue, see the APC Application Notes related to the specific blade server brand. After planning the application density of the blade server according to the five main blade server application methods described above, the results are shown in Table 2.

Table 2 shows that among the 30 different combinations of power density and application methods, there are about 11 combinations and 7 critical combinations-a total of 18 more practical combinations of applications. To choose the * solution, data such as thousands of user preferences, constraints and existing conditions must be compared with these 18 applications. This comparison requires extensive analysis and follows many rules, and the process can be carried out like a software operation. However, there is no detailed description in this white paper.

In the process of developing tools for this analysis, APC provides some key lessons that have been observed over a long period of time in practice:

If more than 25% of the total number of blade server cabinets need to be installed in the room, the power and cooling systems of the existing data center may need to be completely revamped. This means that if the number of installations reaches this limit, users will need to rebuild a computer room, otherwise the data center will have to be shut down for a period of time for system transformation.

If the existing data center plans to install 1 to 5 blade server cabinets, then in order to reduce the impact on the normal operation of the data center to *, while reducing installation costs, it is most appropriate to install at 25% or 50% of the saturated density (for example, up to 3 racks in each cabinet). For most data centers, the cost of achieving very high power density is much higher than the space cost of adding several cabinet locations.

The current data centers generally provide heat dissipation and power supply for the system equipment as a whole, and the auxiliary heat dissipation scheme can improve the application density at a lower cost and achieve a predictable heat dissipation effect.

A method not recommended

Here are some methods and practices that data center managers often use, but these methods are flawed, do not help to solve the problem, and often make the situation worse.

Lower the air temperature. Users usually lower the air temperature of the computer room by lowering the temperature setting of the air conditioner in the computer room, so as to solve some hot spots in the data center. This is the easiest and worst way for users to operate. Doing so will reduce the capacity of the air conditioning system, greatly increase the water consumption of the humidifier, and greatly reduce the operational efficiency of the data center (as a result, it will increase the electricity bill on your bill). All this will happen, and the problem will not be solved at all, because it is a problem of air flow, not air temperature.

Floor grille. Another plausible measure is to replace the ventilated tiles that raise the floor with grille with larger pores. The appearance of this grille is not the perforated floor tile we are familiar with, but a bit like a furnace grate. This method can be helpful for isolated cabinets, but it can have serious side effects-especially if the floor tiles are heavily used. The use of these floor tiles in data centers usually results in reduced airflow in other areas, but more importantly, these grille can cause significant and unpredictable changes in the airflow between the tiles. This issue is described in detail in APC White Paper 46 "cooling Strategies for Ultra High density cabinets and Blade servers".

The top fan of the cabinet. It is common to install fans on top of cabinets-although these fans are of no benefit to a well-designed IT cabinet. The reason for the overheating of the server is not in the interior of the cabinet, but in the hot air at the entrance to the front of the server. These fans can only generate more heat and even reduce the heat dissipation capacity of a well-designed data center. Many users determine the specifications of the fan according to the traditional specifications when the purpose is not clear. There are also some effective fan aids that come with the cabinet, which are described in more detail in APC White Paper 42, "Ten steps to solve the heat dissipation problems caused by the application of high-density servers."

Isolated cabinet. Sometimes users will list the cabinets separately from the whole row of cabinets, trying to reduce the density of the cabinets within a certain range, so that the air flow of the ventilation floor tiles can come into more contact with the cabinets. But this method allows the hot air discharged by the equipment to flow back around the cabinet to the air intake of the server. The overall effect is not very good. A better approach is to keep the cabinet in a hot channel and cold channel arrangement, separate the blade server cabinets with a partition without load, widen the cold channel, and use auxiliary heat dissipation equipment and / or hot channel sealing systems to enhance heat dissipation performance.

The above is all the contents of this article "how to dissipate heat from blade servers". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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