Abstract:
A server Input/Output (I/O) drawer for holding one or more communication cards and one or more I/O cards includes an outer housing, a back plane within the outer housing that divides the drawer into a front portion and back portion, the back plane including a front side and a backside and configured to receive the one or more I/O cards and the one or more communications cards, and an air movement device (AMD) disposed within the front portion, a distribute current assembly (DCA) that receives a voltage from an external source and supplies power, through the backplane, to the AMD.

Description:
BACKGROUND 
       [0001]    The present invention relates to servers and, more specifically, to drawers for holding server input/output cards. 
         [0002]    Input/output (I/O) hubs are often used in server computing devices to allow multiple I/O devices to be connected to the server computing device and manage the I/O operations performed between the I/O devices and the server computing device&#39;s processors, memory, and other resources. Typically, such I/O hub adapters are provided in the host system and are coupled to remote I/O drawers, in which I/O adapters (e.g., PCI or PCI-X adapters) and/or disk devices may be installed, through cabling links, e.g., Remote Input/Output (RIO) cabling links. The I/O drawers typically contain two I/O planars having slots and/or disk bays into which I/O adapter cards may be installed. 
         [0003]      FIG. 1  is an exemplary diagram illustrating a server computing system. As shown in  FIG. 1 , the server computing system  100  includes server computing device  110  having a system frame  115  into which a plurality of operating components are installed. These operating components include a bulk power assembly  120 , a central electronics complex (CEC)  130  in which the processors, memory, and I/O hub adapters are provided, and a plurality of I/O drawers  140 . 
         [0004]    The I/O drawers  140  each have two I/O planars (not shown) which each have a plurality of ports and/or SCSI interfaces with which I/O devices may be coupled, e.g., PCI or PCI-X adapters, hard disks, and the like. The I/O planars of the I/O drawers  140  are coupled to the I/O hub adapters of the CEC  130  via communication cable links, e.g., RIO-2 cable links. The CEC  130 , for purposes of the present description, may constitute the “host system,” with the I/O drawers being remote from the host system such that communication between the host system and the I/O devices coupled to the I/O drawers  140  is facilitated by these cable links. 
       SUMMARY 
       [0005]    According to one embodiment of the present invention, a server Input/Output (I/O) drawer for holding one or more communication cards and one or more I/O cards is disclosed. The drawer of this embodiment includes an outer housing and a back plane within the outer housing that divides the drawer into a front portion and back portion. The back plane includes a front side and a backside and is configured to receive the one or more I/O cards and the one or more communications cards. The drawer of this embodiment also includes an air movement device (AMD) disposed within the front portion and a distribute current assembly (DCA) that receives a voltage from an external source and supplies power, through the backplane, to the AMD. 
         [0006]    According to another embodiment of the present invention, a drawer for holding one or more communication cards and one or more I/O cards server is disclosed. The drawer of this embodiment includes an outer housing and a back plane within the outer housing that divides the drawer into a front portion and back portion. The back plane includes a front side and a backside and is configured to receive the one or more I/O cards and the one or more communications cards in a front receiving area and a back receiving area. The drawer of this embodiment also includes an air movement device (AMD) disposed within the front portion and above the front receiving area and a distributed current assembly (DCA) to provide power to the backplane, the DCA disposed within the back portion and below the back receiving area. 
         [0007]    Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with the advantages and the features, refer to the description and to the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0008]    The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The forgoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0009]      FIG. 1  is an exemplary diagram illustrating a server computing system; 
           [0010]      FIG. 2  is a perspective view of a drawer according to one embodiment; 
           [0011]      FIG. 3  shows a side view of drawer  300  according to one embodiment; and 
           [0012]      FIG. 4  shows a topological view of a backplane  402  according to one embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    In some configurations of the I/O drawers  140  ( FIG. 1 ) problems may exist. These problems, while not catastrophic, may limit usage of the drawers  140  in some situations. For example, the I/O drawers  140  may have limitations with internal bandwidth and power that does not allow support of new high performance I/O adapters. The I/O adapter  140  may also fail to provide power management capability to reduce overall power consumption or utilize proprietary internal buses versus industry technology (e.g., PCIe bus and switches). Further, some I/O drawers do not provide efficient cooling or may not include native “hardware” attachment of industry standard adapters or accelerators. 
         [0014]    In view of these shortcomings, embodiments of the present invention are directed to an I/O drawer. The drawer of the present invention may include improved air flow due to the configuration of the horizontal redundant Air Moving Devices (AMD) (e.g., fans). This may include monitoring internal card temperatures and adjusting AMD speed for optimum power and reliability across the drawer. The drawer may also include a bidirectional fail-over that allows an I/O port to be connected to the host through redundant paths. In one embodiment, the path is front to back through the backplane of the drawer. Embodiments of the I/O drawer of the present invention may allow a service subsystem of the drawer to turn off a single card or single channel port, when function is unused to save power. 
         [0015]      FIG. 2  shows a perspective view of a drawer  200  according to one embodiment. The drawer  200  may be, for example, an I/O drawer but it not so limited. The drawer  200  includes a front portion  202  and a back portion  204 . Both the front portion  202  and the back portion  204  include slots to receive various cards. The slots may be arranged next to one another and be referred to herein as “card receiving areas.” In one embodiment, both the front portion  202  and the back portion  204  include card receiving areas. 
         [0016]    For example, one or both of the front portion  202  or the back portion  204  may receive I/O cards  206  in the card receiving areas. The I/O cards  206  are received in slots. Each slot may include a connection to a back plane  212  that separates the front portion  202  from the back portion  204 . 
         [0017]    The I/O cards  206  may include one or more ports  208  for connection to peripheral devices (not shown) such as data storage devices. Both the front portion  202  and the back portion  204  may include I/O cards  206  while in operation. 
         [0018]    The drawer  200  may also include slots in the card receiving areas for receiving one or more communications cards  210 . The communications cards  210  acts as a go between the computing device and the I/O cards  206 . In one embodiment, the communications card  210  is a PCI or PCIe fanout card. In one embodiment, each communication card  210  provide communications for up to eight I/O cards  206  while in operation. 
         [0019]    Both the I/O cards  206  and the communications card  210  may be coupled to the backplane  212 . A backplane (or “backplane system”) is a circuit board (usually a printed circuit board) that connects several cards in parallel to each other. Information to be provided to an individual I/O card  206  is received from the computing device by the communications card  210  and routed through the backplane  212 . In one embodiment, the back plane may provide multiple power connections to the cards in the drawer  200 . For example, the backplane  212  may provide both 3.3V and 12V power. 
         [0020]    In one embodiment, the drawer  200  may also include one or more flexible support processor (FSP) cards  214 . The FSP cards  214  control operation of the backplane  212  and the drawer  200  as a whole. The FSP cards  214 , I/O cards  206  and communication cards  210  may be collectively referred to as “cards.” 
         [0021]    The drawer  200  may also include one or more AMDs  216 . The AMDs  216  may be, for example, fans. Operation of the AMDs  216  may be controlled, for example, by the FSP card. In one embodiment, the AMDs are located above the cards in the front portion  202  of the drawer  200 . The AMDs may provide redundant functional air flow paths for air to pass through and cool the cards and may be interconnected to provide failover protection. In one embodiment, the AMDs may be field replaceable units (FRUs) to enable repair and verification in the field. 
         [0022]    The drawer  200  may also include one or more distributed current assemblies  218  (DCAs). The DCAs convert high voltage power to the logic levels (e.g., 3.3V and 12V) provided to the cards through the backplane  212 . In one embodiment, the DCAs  218  are interconnected to provide failover protection. 
         [0023]      FIG. 3  shows a side view of drawer  300  according to one embodiment. The drawer  300  may include an outer housing  302 . The outer housing  302  may support the elements of the drawer and allow it to be mounted into a cage. The drawer  300  may include front portion  304  and back portion  306 . The front portion  304  is separated from the back portion  306  by a backplane  308 . The backplane  308  may extend only a portion of the distance from a bottom  310  of the housing  302  to a top  312  of the housing  302 . 
         [0024]    The backplane  308  may include connections for cards on both sides thereof. Accordingly, the front portion  304  may include a front card receiving area  314 . Similarly, the back portion  306  may include back card receiving area  316 . Both the front card receiving area  314  and the back card receiving area  316  may include any combination of cards. In one embodiment, both the front card receiving area  314  and the back card receiving area  316  are configured and arranged to receive and provide connections for 16 I/O cards, two communications cards (e.g., PCI or PCIe switch cards), and one FSP card. 
         [0025]    In one embodiment, the drawer  300  may include an air inlet chamber  318 . The air inlet chamber may include an air intake  320  located on a front side  322  of the drawer  300 . The air inlet chamber  318  may be located between the front card receiving area  314  and the bottom  310  of the housing  302 . The front portion  304  may also include one or more AMD&#39;s  324  located over the front card receiving area  314 . In one embodiment, the AMD&#39;s  324  are separated from the front card receiving area  314  by a first air plenum  326 . 
         [0026]    In one embodiment, the AMD&#39;s  324  such at least a portion thereon contacts the backplane  308 . The AMD&#39;s  324  may be arranged such that they draw air from below. 
         [0027]    In one embodiment, the back portion  308  may include a second air plenum  328 . The second air plenum  328  may separate the back card receiving area  316  from the top  312  of the housing  302 . In one embodiment, the second air plenum  328  may provide for an air path between the housing  302  and the backplane  308 . A third plenum  330  may be located below the back card receiving area  316 . 
         [0028]    In one embodiment, the drawer  300  may also include one or more DCA&#39;s  332  located in the back portion  306 . The DCA  332  receives power from an external source at a high voltage. The DCA  332  coverts at a least a portion of this power into logic level voltages (e.g., 3.3V or 12V) and provides it to the backplane  308 . These logic level voltages may be provided to I/O cards when such are installed in either or both of the front card receiving area  314  or the back card receiving area  316 . The DCA  332  may include an exhaust  334 . 
         [0029]    In one embodiment, the backplane  308  may also include means for carrying higher voltages. In such an embodiment, the AMDs  324  may receive power from, and be controlled by, the DCA  332  through the backplane  308 . In one embodiment, the AMDs  324  may receive at least 350V DC from the DCA  332  through the backplane  308 . 
         [0030]    In operation, the AMDs  324  cause air to be drawn into the air inlet chamber  318  though the air intake  320 . The air is drawn upward through the front card receiving area  314  and cools any cards disposed therein. The AMDs  324  cause the air to travel through the first air plenum  326  and expel it into the second air plenum  328 . From the second air plenum  328 , air travels through the back card receiving area  316  and cools any cards located therein. The air also travels from the back card receiving area  316  through the third plenum  330  and through the DCAs  332  where it is discharged through exhaust  334 . The arrows in  FIG. 3  generally show the flow air through the drawer  300  when the AMDs  324  are operational. It shall be understood that additional elements may be located between the elements shown in  FIG. 3  without departing from the spirit of the invention disclosed herein. In addition, some or all of the air plenums may be eliminated. 
         [0031]    In one embodiment, the AMDs  324  may provide redundant functional airflow paths for air to pass through and cool the cards and may be interconnected to provide failover protection. In one embodiment, the DCAs  332  are interconnected to provide failover protection. 
         [0032]      FIG. 4  shows a topological view of a backplane  402  according to one embodiment. The backplane  402  is coupled to several cards. In one embodiment, the backplane  402  may provide one or more logic level voltages to the cards. 
         [0033]    In more detail, the backplane  402  may, in one embodiment, include four communications cards  404 ,  406 ,  408  and  410 . Of course the number of communication cards may be varied. Each communication card  404 ,  406 ,  408  and  410  is coupled through the backplane to one or more I/O cards. For example, the first communication card  404  is coupled to a first group of I/O cards  405 , the second communication card  406  is coupled to second group of I/O cards  407 , the third communication card  408  is coupled to a third group of I/O cards  409  and the fourth communication card  410  is coupled to a fourth group of I/O cards  411 . The number of I/O cards each communication card is coupled to may vary. 
         [0034]    Each side of the backplane  402  may be coupled to an FSP. For example the first side  401  of the back plane may be coupled to a first FSP  412  and the second side  403  of the backplane  402  may be coupled to a second FSP  414 . 
         [0035]    In one embodiment, a communication card coupled to the first side  401  may be coupled to a communication card coupled to the second side  403 . For example, the first communication card  404  may be coupled to the third communication card  408  and the second communication card  406  may be coupled to the fourth communication card  410 . The coupling may be provided, for example, by a bus. For example, the first bus  412  couples the first communication card  404  to the third communication card  408  and the second bus  414  couples the second communication card  406  to the fourth communication card  410 . The coupling allows for communication in the event that one of the communication cards fails. In one embodiment, in a communication card on the front side of a drawer is coupled to a communication card on the back side of a drawer through the backplane  402 . 
         [0036]    The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof. 
         [0037]    The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated. 
         [0038]    The flow diagrams depicted herein are just one example. There may be many variations to this diagram or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order or steps may be added, deleted or modified. All of these variations are considered a part of the claimed invention. 
         [0039]    While the preferred embodiment to the invention had been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.