WO2015038410A1

WO2015038410A1 - Cooling system management for server facility

Info

Publication number: WO2015038410A1
Application number: PCT/US2014/054171
Authority: WO
Inventors: Luis Noel Rodriguez Ruiz; Wilson Manuel Toro Belen; Abner Candelario
Original assignee: Microsoft Corporation
Priority date: 2013-09-10
Filing date: 2014-09-05
Publication date: 2015-03-19
Also published as: CN105580504A; RU2016108115A3; JP2016538524A; RU2016108115A; US20150073606A1; EP3045026A1

Abstract

A Computer Room Air Handler (CRAH) Unit conditions and provides cooling air to a first zone. A second zone collects return air from the first zone, where multiple servers are positioned between the first zone and the second zone such that air heated by the servers is pushed into the second zone. The first zone is bound from the second zone by one or more racks housing the servers and insulating materials in an area between each server to prevent the cooling air in the first zone from mixing with the return air in the second zone. A third zone, representing a remaining area of the server facility, is maintained at a predefined temperature, where the temperature is higher than a temperature of the first zone and lower than a temperature of the second zone.

Description

COOLING SYSTEM MANAGEMENT FOR SERVER FACILITY

BACKGROUND

[0001] A server facility may include a collection of computer systems consisting of primary and backup servers. A server facility may also include environmental controls and security devices to protect the data housed within the systems of the server facility. The servers are generally stored within a rack. In one rack there may be a multitude of servers and a server facility may have a large quantity of racks.

[0002] Each server has a specific heat output based on the amount of power the server consumes, therefore a cooling system within the server facility may be critical to the maintenance and function of these servers. Common characteristics of traditional cooling approaches may include perimeter cooling, where Computer Room Air Conditioning (CRAC) units are placed on the outer perimeter of the racks, and a raised floor, where cold air is delivered to the racks via a plenum under the floor. The systems of traditional cooling approaches may waste a significant amount of energy due to hot air generated by the servers mixing with the cold air delivered to the racks, causing the CRAC units to consume more energy to cool the air to lower temperatures to compensate for the mixing.

[0003] As more enterprises start using practical servers and sharp edge servers within their server facilities, an increase in the quantity of power consumed per server may result in an overall increased heat output within the server facilities. With higher energy costs and increased energy consumption rates, more efficient cooling systems may need to be implemented within server facilities.

SUMMARY

[0004] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to exclusively identify key features or essential features of the claimed subject matter, nor is it intended as an aid in determining the scope of the claimed subject matter.

[0005] Embodiments are directed to a method and a temperature management system to manage a cooling system in a server facility. According to some embodiments, a

Computer Room Air Handler (CRAH) Unit may condition and provide cooling air to a first zone. A second zone may collect return air from the first zone, where multiple servers may be positioned between the first zone and the second zone such that heated air by the servers may be pushed into the second zone enabling air collection. The first zone may be bound from the second zone by one or more racks housing the servers and insulating materials in an area between each server to prevent the cooling air in the first zone from mixing with the return air in the second zone. According to other

embodiments, a third zone, representing a remaining area of the server facility, may be maintained at a predefined temperature, where the temperature may be higher than a temperature of the first zone and lower than a temperature of the second zone.

[0006] These and other features and advantages will be apparent from a reading of the following detailed description and a review of the associated drawings. It is to be understood that both the foregoing general description and the following detailed description are explanatory and do not restrict aspects as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. 1 includes a conceptual diagram illustrating an example temperature management system in a server facility, where embodiments may be implemented;

[0008] FIG. 2 illustrates in greater detail a first zone and a second zone of an example temperature management system in a server facility;

[0009] FIG. 3 includes a conceptual diagram illustrating an alternate embodiment for a temperature management system in a server facility;

[0010] FIG. 4 illustrates a system to manage a cooling system in a server facility;

[0011] FIG. 5 is a block diagram of an example computing operating environment, where embodiments may be implemented; and

[0012] FIG. 6 illustrates a logic flow diagram of a method to manage a cooling system in a server facility, according to embodiments.

DETAILED DESCRIPTION

[0013] As briefly described above, a Computer Room Air Handler (CRAH) Unit may condition and provide cooling air to a first zone. A second zone may collect return air from the first zone, where multiple servers may be positioned between the first zone and the second zone such that heated air by the servers may be pushed into the second zone enabling collection. The first zone may be bound from the second zone by one or more racks housing the servers and insulating materials in an area between each server to prevent cooling air in the first zone from mixing with return air in the second zone.

[0014] In the following detailed description, references are made to the accompanying drawings that form a part hereof, and in which are shown by way of illustrations specific embodiments or examples. These aspects may be combined, other aspects may be utilized, and structural changes may be made without departing from the spirit or scope of the present disclosure. The following detailed description is therefore not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents.

[0015] While some embodiments will be described in the general context of program modules that execute in conjunction with an application program that runs on an operating system on a personal computer, those skilled in the art will recognize that aspects may also be implemented in combination with other program modules.

[0016] Generally, program modules include routines, programs, components, data structures, and other types of structures that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that embodiments may be practiced with other computer system configurations, including hand-held devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, minicomputers, mainframe computers, and comparable computing devices. Embodiments may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.

[0017] Some embodiments may be implemented as a computer-implemented process (method), a computing system, or as an article of manufacture, such as a computer program product or computer readable media. The computer program product may be a computer storage medium readable by a computer system and encoding a computer program that comprises instructions for causing a computer or computing system to perform example process(es). The computer-readable storage medium is a computer- readable memory device. The computer-readable storage medium can for example be implemented via one or more of a volatile computer memory, a non- volatile memory, a hard drive, a flash drive, a floppy disk, or a compact disk, and comparable hardware media.

[0018] Throughout this specification, the term "platform" may be a combination of software and hardware components for operating an air cooling management system. Examples of platforms include, but are not limited to, a hosted service executed over a plurality of servers, an application executed on a single computing device, and comparable systems. The term "server" generally refers to a computing device executing one or more software programs typically in a networked environment. However, a server may also be implemented as a virtual server (software programs) executed on one or more computing devices viewed as a server on the network. More detail on these technologies and example operations is provided below.

[0019] FIG. 1 includes a conceptual diagram illustrating an example temperature management system in a server facility, where embodiments may be implemented. As illustrated in diagram 1, the system may include a first zone 102, a second zone 108, a third zone 114, and a Computer Room Air Handler (CRAH) unit 110. Multiple servers

106 may be positioned in one or more racks 104 that form a boundary 105 between the first zone 102 and the second zone 108. The first zone may be in contact with front ends of multiple servers and the second zone may be in contact with back ends of the servers.

[0020] The CRAH may be configured to provide cooling air 103 to the first zone, and as the CRAH unit 110 provides the cooling air 103 to the first zone 102, the servers 106 may take in the cooling air 103 through the front ends of the servers and circulate the cooling air within the servers. As the cooling air circulates within the servers, the air may be heated and pushed through the back ends of the servers into the second zone 108, where the second zone 108 may collect the heated air, or return air 107. The first zone 102 may be shaped substantially as a corridor with one or more racks forming opposing walls, and may be insulated with insulating materials to prevent the cooling air 103 in the first zone 102 from mixing with the return air 107 in the second zone 108. A ceiling of the first zone 102 and an area between each server in the one or more racks 104 at the boundary 105 of the first zone 102 and the second zone 108 may be insulated with the insulating materials.

[0021] A temperature monitoring system, coupled to a management controller, may measure the air temperature of each zone and an external environment. The temperature monitoring system may compare the temperature of the return air 107 in the second zone 108 to the temperature of air in the external environment. If air in the external

environment is higher in temperature than the return air 107 in the second zone 108, the management controller may provide instructions to a switch 116 to provide the return air

107 in the second zone 108 to the CRAH unit 110. In an alternate embodiment, if air in the external environment is lower in temperature than the return air in the second zone, the management controller may provide instructions to the switch to expel the return air into the external environment and take in air from the external environment to provide to the CRAH unit.

[0022] The CRAH unit 110 may then condition the cooling air 103 to be provided to the first zone 102 using one or more of cooling coils and chilled water. The third zone 114 may represent a remaining area of the server facility. The third zone 114 may be maintained at a predefined temperature, where the temperature may be higher than a temperature of the first zone 102 and lower than a temperature of the second zone 108.

[0023] The third zone 114 may include fire suppression, security, and/or monitoring systems. The large amount of power consumed by the servers, particularly in server facilities with a substantial amount of racks, may present a serious risk of fire due to the consequential heat output. While the cooling system may serve as a preventative method to reduce the risk of fire, a fire suppression system may be essential. A fire suppression system may include one or more heat sensors and/or wiring for detection, and a combination of dry chemicals and/or wet agents, such as a sprinkler system, to extinguish a fire.

[0024] An additional risk associated with a server facility is one of security. Some or all of the servers may store confidential or sensitive data, such as corporate data, financial data, or medical data that may be irreplaceable and may be detrimental if disclosed to an unauthorized party. Security systems, such as cameras and alarms, may be implemented to ensure the containment of the data. Cameras may further be useful in manual detection of fire, in case of a malfunction of the fire suppression system. Monitoring systems may also be present in the third zone 114, such as the temperature monitoring system discussed above.

[0025] The example system in FIG. 1 has been described with specific components, tasks of components, and arrangements of components. Embodiments are not limited to the system according to this example configuration. A temperature management system in a server facility may be implemented in configurations employing fewer or additional components, and performing other tasks. Furthermore, temperature management systems in other facilities may be implemented in a similar manner using the principles described herein.

[0026] FIG. 2 illustrates in greater detail a first zone and a second zone of an example temperature management system in a server facility. As discussed in FIG. 1, the temperature management system may include multiple servers 206 positioned in one or more racks 204 that form a boundary 205 between a first zone 202 and a second zone 208. The first zone 202 may be in contact with front ends of the servers, and the second zone 208 may be in contact with back ends of the servers. The system may also include a third zone 214 which may be maintained at a predefined temperature, where the temperature is higher than a temperature of the first zone 202 and lower than a temperature of the second zone 208. [0027] As cooling air 203 is provided to the first zone 202, the servers 206 may take in the cooling air 103 through a first fan 210 in the front ends of the servers and circulate the cooling air within the servers. As the cooling air circulates within the servers, the air may become heated as a result of the servers' heat output. The servers 206 may push the heated air through a second fan 212 in the back ends of the servers into the second zone 208, where the second zone 208 may collect the heated air, or return air 207.

[0028] As previously discussed, the first zone 202 may be shaped substantially as a corridor with one or more racks forming opposing walls, and may be insulated with insulating materials to prevent the cooling air 203 in the first zone 202 from mixing with the return air 207 in the second zone 208. A ceiling of the first zone 202 and an area between each server in the one or more racks 204 at the boundary 205 of the first zone 202 and the second zone 208 may be insulated with the insulating materials. The insulating materials may be selected based on local, state, and federal regulations as well as industry standards. For example, regulations and industry standards may mandate use of materials with particular properties or materials of particular quality to ensure safety and efficiency. The insulating materials may be further selected based on fire suppression and security capabilities. For example, a transparent material may be used to insulate the first zone, enabling a security system to monitor the servers for intrusion or to easily detect a fire. In another example, aluminum may be used in a structural frame of the first zone due to the metal's fire suppression capabilities.

[0029] Insulating the first zone 202 may reduce energy consumption rates of the server facility. By preventing the mixture of cooling air 203 with higher temperature air, such as the return air 207 and air in the third zone, a Computer Room Air Handler (CRAH) unit may consume less energy conditioning the cooling air to an appropriate temperature to provide to the first zone 202. The temperature of the cooling air may be in a range from about 50 °F to 75 °F.

[0030] For example, employing current solutions, the CRAH unit may provide air to a cooling area, analogous to the first zone 202, at a temperature of about 68° F to compensate for the air temperature being raised as the air mixes with higher temperature air from other areas of the facility within the cooling area. In contrast, employing the proposed solution, the CRAH unit may provide cooling air 203 to the first zone 202 at a temperature of only 78° F as there is no need to compensate for mixing of the cooling air 203 with higher temperature air, such as the return air 207 in the second zone 208 and air in the third zone 214. The ten degree difference in temperature may amount to a significant reduction in energy consumption, and consequently, a significant reduction in energy costs.

[0031] Referring to FIG. 3, a conceptual diagram 300 illustrates an alternate

embodiment for a temperature management system in a server facility. A temperature monitoring system, coupled to a management controller, may measure the air temperature in each zone and an air temperature in an external environment 312. The temperature monitoring system may compare the air temperature in the external environment 312 to the temperature of return air 307 in a second zone 308. In response, the management controller may communicate with a switch 302 to provide instructions dependent on the air temperature comparison.

[0032] In a first scenario, air in the external environment 312 may be lower in temperature than the return air 107 in the second zone 108. In response, the management controller may provide instructions to the switch 302 to expel the return air 307 into the external environment 312 via an output pipe 304 and take in air 311 from the external environment 312 via an intake pipe 306. The air 311 from the external environment 312 may then be provided to the CRAH unit 110.

[0033] In a second scenario, air in the external environment 312 may be higher in temperature than the return air 307 in the second zone 308. The management controller may provide instructions to the switch 302 to provide the return air 307 in the second zone 308 to the CRAH unit 310.

[0034] FIG. 4 illustrates a system to manage a cooling system in a server facility.

System 400 may include a management controller 410, a first zone 412, a second zone 414, a Computer Room Air Handler (CRAH) unit 416, an external environment 418, and a third zone 420. The management controller 410 may be operated by human control, or may be directed by a remote controller 402 via network 404. Data associated with controlling the different processes of managing a cooling system may be stored at and/or received from data stores 430.

[0035] Servers may be positioned in one or more racks that form a boundary between the first zone 412 and the second zone 414. The first zone 412 may be in contact with front ends of the servers, enabling the servers to take in cooling air through a first fan in the front ends of the server as the cooling air is provided to the first zone 412. The servers may circulate the cooling air within the servers and push heated return air through a second fan in the back ends of the servers, where the second zone 414 may be in contact with the back ends of the servers to collect the return air. [0036] Return air in the second zone 414 may be provided to the CRAH unit 416 or alternately may be expelled to the external environment 418. The management controller 410 may be coupled to a temperature monitoring system of the server facility and may communicate with a switch to provide instructions based on measurements and

comparisons made by the temperature monitoring system. The temperature monitoring system may measure and compare the temperature of the return air in the second zone 414 to the air temperature in an external environment 418. If air in the external environment 312 is a higher temperature than the return air in the second zone 414, the management controller may provide instructions to the switch to provide the return air from the second zone 414 to the CRAH unit 416. Alternately, if air in the external environment 418 is lower in temperature than the return air in the second zone 414, the management controller may provide instructions to the switch to expel the return air into the external environment 418. Further instructions may be provided to the switch to take in air from the external environment 418. The air from the external environment 418 may then be provided to the CRAH unit 416.

[0037] The CRAH unit 416 may then condition cooling air using one or more of cooling coils and chilled water. Once the air is sufficiently conditioned, the cooling air may be provided to the first zone 412.

[0038] The third zone 420 may represent a remaining area of the server facility and be maintained at a predefined temperature, where the temperature may be higher than a temperature of the first zone 412 and lower than a temperature of the second zone 414. The third zone 420 may include fire suppression, security, and/or monitoring systems controlled by the management controller 410.

[0039] The examples in FIG. 1 through 4 have been described with specific systems including components, tasks of components, and arrangement of components.

Embodiments are not limited to systems according to these example configurations.

Management of a cooling system in a server facility may be implemented in

configurations using other types of systems including components, tasks of components, and arrangement of components in a similar manner using the principles described herein.

[0040] FIG. 5 and the associated discussion are intended to provide a brief, general description of a suitable computing environment in which embodiments may be implemented. With reference to FIG. 5, a block diagram of an example computing operating environment for an application according to embodiments is illustrated, such as computing device 500. In a basic configuration, computing device 500 may be any portable computing device with wireless communication capabilities, which may include touch and/or gesture detection capability in some examples, and include at least one processing unit 502 and system memory 504. Computing device 500 may also include multiple processing units that cooperate in executing programs. Depending on the exact configuration and type of computing device, the system memory 504 may be volatile (such as RAM), non-volatile (such as ROM, flash memory, etc.) or some combination of the two. System memory 504 typically includes an operating system 505 suitable for controlling the operation of the platform, such as the WINDOWS ®, WINDOWS

MOBILE®, or WINDOWS PHONE® operating systems from MICROSOFT

CORPORATION of Redmond, Washington. The system memory 504 may also include one or more software applications such as a management controller application 522, and a switch module 524.

[0041] Management controller Application 522, coupled to a temperature monitoring system, may communicate with the switch module 524 to provide instructions, the instructions dependent upon measurements and comparisons made by the temperature monitoring system. The temperature monitoring system may measure an air temperature for each zone in the server facility and an air temperature of an external environment, and may compare the air temperature of a second zone to an air temperature of the external environment. In response to determination that air in the external environment is a higher temperature than return air in the second zone, the management controller application 522 may provide instructions to the switch module 524 to provide the return air to the CRAH unit. Alternately, in response to determination that air in the external environment is a lower temperature than return air in the second zone, the management controller application 522 may provide instructions to the switch module 524 to expel the return air to the external environment. The management controller application 522 may further provide instructions to the switch module 524 to take in air from the external environment and provide the air from the external environment to a CRAH unit. Management controller application 522 and switch module 524 may be separate applications or integrated modules of a hosted service. This basic configuration is illustrated in FIG. 5 by those components within dashed line 508.

[0042] Computing device 500 may have additional features or functionality. For example, the computing device 500 may also include additional data storage devices (removable and/or non-removable) such as, for example, magnetic disks, optical disks, or tape. Such additional storage is illustrated in FIG. 5 by removable storage 509 and non- removable storage 510. Computer readable storage media may include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data. System memory 504, removable storage 509 and non-removable storage 510 are all examples of computer readable storage media. Computer readable storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by computing device 500. Any such computer readable storage media may be part of computing device 500. Computing device 500 may also have input device(s) 512 such as keyboard, mouse, pen, voice input device, touch input device, an optical capture device for detecting gestures, and comparable input devices. Output device(s) 514 such as a display, speakers, printer, and other types of output devices may also be included. These devices are well known in the art and need not be discussed at length here.

[0043] Some embodiments may be implemented in a computing device that includes a communication module, a memory device, and a processor, where the processor executes a method as described above or comparable ones in conjunction with instructions stored in the memory device. Other embodiments may be implemented as a computer readable memory device with instructions stored thereon for executing a method as described above or similar ones. Examples of memory devices as various implementations of hardware are discussed above.

[0044] Computing device 500 may also contain communication connections 516 that allow the device to communicate with other devices 518, such as over a wired or wireless network in a distributed computing environment, a satellite link, a cellular link, a short range network, and comparable mechanisms. Other devices 518 may include computer device(s) that execute communication applications, web servers, and comparable devices. Communication connection(s) 516 is one example of communication media.

Communication media can include therein computer readable instructions, data structures, program modules, or other data. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. [0045] Example embodiments also include methods. These methods can be

implemented in any number of ways, including the structures described in this document. One such way is by machine operations, of devices of the type described in this document.

[0046] Another optional way is for one or more of the individual operations of the methods to be performed in conjunction with one or more human operators performing some. These human operators need not be collocated with each other, but each can be only with a machine that performs a portion of the program.

[0047] FIG. 6 illustrates a logic flow diagram for process 600 of a method to manage a cooling system in a server facility according to embodiments. Process 600 may be implemented on a server or other system.

[0048] Process 600 begins with operation 610, where cooling air may be provided to a first zone. The first zone may be bounded from a second zone by one or more racks housing multiple servers and insulating materials between each server within the one or more racks at the boundary between the first zone and the second zone. The first zone may be in contact with front ends of the servers, enabling the servers to take in the cooling air provided to the first zone and circulate the cooling air within the servers. As the cooling air is circulated within the servers, the servers may heat the air and push return air into a second zone. At operation 620, the heated return air may be collected in the second zone.

[0049] At operation 630, the return air in the second zone may be provided to a CRAH unit in response to determination that air in an external environment is a higher temperature than the return air in the second zone. At optional operation 640, the return air may alternately be expelled into the external environment or re-directed to another space that may need to be warmed up, in response to determination that air in the external environment is a lower temperature than return air in the second zone. Air in the external environment may then be taken in and provided to the CRAH unit.

[0050] At operation 650, the CRAH unit may condition the cooling air using one or more of cooling coils and chilled water. At operation 660, once sufficiently conditioned, the CRAH unit may provide the cooling air to the first zone.

[0051] The operations included in process 600 are for illustration purposes.

Management of a cooling system in a server facility may be implemented by similar processes with fewer or additional steps, as well as in different order of operations using the principles described herein. [0052] The above specification, examples and data provide a complete description of the manufacture and use of the composition of the embodiments. Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims and embodiments.

Claims

A method to manage a cooling system in a server facility, the method comprising: providing cooling air from a Computer Room Air Handler (CRAH) unit to a

first zone; and

collecting return air from the first zone in a second zone, wherein a plurality of servers are positioned between the first zone and the second zone such that air heated by the servers is pushed into the second zone and the first zone is substantially thermally insulated from a remainder of the server facility.

The method of claim 1 , wherein the plurality of servers are positioned in one or more racks that form a boundary between the first zone and the second zone.

The method of claim 2, wherein the first zone is in contact with front ends of the plurality of servers and the second zone is in contact with back ends of the plurality of servers.

The method of claim 3, further comprising:

causing the plurality of servers to take in the cooling air provided to the first zone through an intake pipe in the front ends of the plurality of servers and circulate the cooling air through the plurality of servers.

The method of claim 1, further comprising:

insulating a ceiling of the first zone with insulating materials, wherein the first zone is shaped substantially as a corridor with one or more racks of servers forming opposing walls.

The method of claim 5, further comprising:

insulating an area between each server in the one or more racks at a boundary of the first zone and the second zone with insulating materials to prevent the cooling air and return air from mixing.

The method of claim 1, further comprising:

employing a temperature monitoring system, wherein the temperature monitoring system measures an air temperature in each zone and an air temperature in an external environment.

8. The method of claim 7, further comprising:

in response to a determination that air in the external environment is at a lower air temperature than return air in the second zone:

expelling the return air in the second zone into the external environment;

taking in the air from the external environment; and

providing the air from the external environment to the CRAH unit.

9. The method of claim 7, further comprising:

in response to a determination that air in the external environment is at a higher air temperature than the return air in the second zone, providing the return air to the CRAH unit.

The method of claim 1, further comprising:

conditioning the cooling air using one or more of cooling coils and chilled water.

A temperature management system for a server facility, the system comprising: a Computer Room Air Handler (CRAH) unit configured to provide cooling air to a first zone;

the first zone bounded from a second zone by one or more racks housing a plurality of servers and insulating materials in an area between each server, wherein the first zone is substantially thermally insulated from a remaining portion of the server facility; and

the second zone configured to collect return air from the first zone, wherein the plurality of servers are positioned between the first zone and the second zone such that heated air by the servers is expelled into the second zone.

The system of claim 11 , wherein the insulating materials are selected based on one or more of local regulations, state regulations, federal regulations, and industry standards.

13. The system of claim 12, wherein the insulating materials are further selected based on fire suppression and security capabilities.

14. The system of claim 11 , wherein the temperature management system further comprises a temperature monitoring system, the temperature monitoring system configured to:

measure an air temperature in each zone and an air temperature in an external environment;

compare the air temperature in the external environment to the air temperature of the return air in the second zone; and

provide one of air from the external environment and the return air to the CRAH unit based on a result of the comparison.

15. A method to manage a cooling system in a server facility, the method comprising:

providing cooling air from a Computer Room Air Handler (CRAH) unit to a first zone, wherein the first zone is substantially thermally insulated from a remaining portion of the server facility;

collecting return air from the first zone in a second zone, wherein a plurality of servers are positioned between the first zone and the second zone such that air heated by the servers is pushed into the second zone; and

maintaining a predefined air temperature in a third zone, wherein the predefined air temperature of the third zone is higher than an air temperature of the first zone and lower than an air temperature of the second zone.