Abstract:
A method of controlling the selection of operating systems at a first instance of user logon on a target device is provided. A network bootstrap program is initiated at the target device and configuration data of the target device is determined. A selection manager is designated based on the configuration data and the selection of a target operating system is controlled with the selection manager prior to executing an operating system at the target device.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to client computers that are bootable over a network and, in particular, client computers that may be serviced by multiple boot servers. More specifically, the present invention relates to a method for remotely managing the means by which a target device may choose its operating system. 
     2. Description of Related Art 
     Some current computing devices include support for pre-boot extensions to download an operating system (OS) from a network to which they are attached. Such target computing devices include computer motherboards, network adapters and boot diskettes. These devices rely on extensions to the bootstrap protocol (BOOTP) and to the dynamic host configuration protocol (DHCP). Such extensions are often termed the preboot execution environment (PXE) and require a DHCP/PXE server and a boot image negotiation layer (BINL) server. 
     BOOTP is a transmission control protocol/Internet protocol (TCP/IP) used by a diskless workstation, network computer (NC) or other target device to obtain its IP address and other network information, such as server address and default gateway. Upon startup, the target device sends out a BOOTP request to the BOOTP server, which returns the required information. The BOOTP request and response use an IP broadcast function, which is able to send messages before a specific IP address for a target device is known. 
     DHCP is software that automatically assigns an IP address to a target device logging onto a TCP/IP network. DHCP eliminates the need for manually assigning permanent IP addresses. 
     PXE enables a client network computer or other target device that lacks a native operating system to locate and acquire a small network bootstrap program (NBP) from a BINL server. The target device may acquire this NBP from a BINL server through a network attachment. PXE also provides a means for running the NPB on the target device. This allows the target device to continue acquiring additional software from the network that may be required to make the target device capable of performing the more complex and useful tasks assigned to it by an enterprise. 
     PXE relies on extensions of DHCP as the means by which the target device locates a BINL server from which to acquire an NPB. A facilitating property of DHCP is that the target device does not need the address of any other computer. The target device performs a DHCP broadcast to discover any PXE proxy server that can recognize that the target device is PXE-capable. The DHCP proxy server sends a DHCP offer to the target device. The offer contains the address of the BINL server from which the target device may obtain a NBP. The target device then obtains the NBP and all necessary software from the boot server via a trivial file transfer protocol (TFTP). 
     Current approaches to selecting the operating system to boot on a target device depend on the BINL server, which is delivered by multiple vendors, such as Intel™, IBM™ and Microsoft™. Each platform has different implementations and behaviors. If a number of different operating systems are available for selection on a particular device, there is no way for an administrator to administer the selection of the operating systems. 
     It would be desirable therefore to provide a method of selecting an operating system that overcomes the above. 
     SUMMARY OF THE INVENTION 
     One aspect of the present invention provides a method of controlling the selection of operating systems at a first instance of user logon on a target device. A network bootstrap program is initiated at the target device and configuration data of the target device is determined. A selection manager is designated based on the configuration data and the selection of a target operating system is controlled with the selection manager prior to executing an operating system at the target device. 
     An operating systems list may be presented to the selection manager. A request for the operating systems list may be received from the selection manager. The target operating system may be selected from the operating systems list with the selection manager. The target operating system may be sent to the target device. The network bootstrap program may be relocated after the target operating system is selected. The target operating system may then be executed on the target device 
     At a subsequent instance of user logon on the target device, a new selection manager may be designated. The selection manager may be, for example, the target device or may be located at a server in communication with the target device. 
     Another aspect of the present invention provides computer program product in a computer usable medium for controlling the selection of operating systems at a first instance of user logon on a target device. The computer program product may include means for executing network bootstrap program code at the target device. The computer program product may also include means for determining configuration data of the target device and means for designating a selection manager based on the configuration data. The computer program product may also include means for controlling the selection of a target operating system with the selection manager prior to executing an operating system at the target device. 
     The computer program product may also include means for presenting an operating systems list to the selection manager. The computer program product may also include means for receiving from the selection manager a request for the operating systems list. The computer program product may also include means for selecting a target operating system from the operating systems list with the selection manager and means for sending the target operating system to the target device. The computer program product may also include means for relocating the network bootstrap program code after the target operating system is selected and means for executing the target operating system on the target device. 
     The computer program product may further include computer readable program code that designates a new selection manager at a subsequent instance of user logon on the target device. 
     Another aspect of the present invention provides a data processing system comprising means for initiating a network bootstrap program at a target device, means for determining configuration data of the target device, means for designating a selection manager based on the configuration data and means for controlling the selection of a target operating system at a first instance of user logon on the target device before an operating system is executed at the target device. 
     The system may also include means for receiving from the selection manager a request for an operating systems list, means for presenting the operating systems list to the selection manager, and means for receiving the selection of the target operating system from the operating systems list with the selection manager. 
     The system may also include means for sending the target operating system to the target device, means for relocating the network bootstrap program after the target operating system is received on the target device, and means for executing the target operating system on the target device. 
     The system may also include means for designating a new selection manager at a subsequent instance of user logon on the target device. 
     The foregoing, and other, features and advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention rather than limiting, the scope of the invention being defined by the appended claims in equivalence thereof. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic diagram of one embodiment of a network of data processing systems in accordance with the present invention; 
     FIG. 2 is a block diagram of one embodiment of a data processing system in accordance with the present invention; 
     FIG. 3 is a block diagram of another embodiment of a data processing system in accordance with the present invention; 
     FIG. 4 is a flow diagram of one embodiment of a method of selecting an operating system in accordance with the present invention; and 
     FIG. 5 is a flow diagram of one embodiment of a method of selecting an operating system continuing the embodiment of FIG.  4 . 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 is a schematic representation of a network of data processing systems in accordance with the present invention at  100 . Network data processing system  100  may be a network of computers in which the present invention may be implemented. Network data processing system  100  may contain a network. Network  102  may be any suitable medium used to provide communications links between various devices and computers connected to or in communication with each other within network data processing system  100 . For example, network  102  may include connections, such as wire connections, wireless communication links or fiber optic cables. 
     In the embodiment of FIG. 1, a server  104  may be in communication with network  102 . Server  104  may provide data, such as boot files, operating system images and applications to network  102  and/or to other components in communication with network  102  as described below. System  100  may also include another server  105  which may be identical to or different from server  104 . Server  105  may also provide data, such as boot files, operating system images and applications to network  102  and/or to other components in communication with network  102  as described below. System  100  may also include additional servers (not shown). 
     One or more storage units, such as storage unit  106  may also be in communication with server  104 ,  105  and/or network  102 . Storage unit  106  may store data, such as boot files, operating system images and applications that may be processed or conveyed by server  104 . Storage unit  106  may also store data to be made available to or process by network  102  and/or to other components in communication with network  102  as described below. 
     In addition, target devices  108 ,  110  and  112  are also in communication with network  102 . These target devices may be, for example, personal computers or network computers. Target devices  108 ,  110 ,  112  may serve as clients to server  104 . Network data processing system  100  may include additional servers, clients and other devices not shown. 
     As seen in FIG. 1, network data processing system  100  may be any suitable system of processing data. For example system  100  may be the Internet. Alternatively, network data processing system  100  may also be any suitable type of network such as, for example, an intranet, a local area network (LAN) or a wide area network (WAN). In one embodiment of the invention, network  102  represents a worldwide collection of networks and gateways that use the TCP/IP suite of protocols to communicate with one another. A backbone of high-speed data communication lines between major nodes or host computers allows communication between thousands of commercial, government, educational and other computer systems that route data and messages. 
     One embodiment of the present invention provides a network environment, which may include a DHCP/PXE proxy server. For example, server  104  may be a DHCPIPXE proxy server. Alternatively, server  105  may be a DHCP/PXE proxy server. System  100  may also include one or more boot servers. For example server  104  or server  105  may serve as a boot server. These boot servers may be collated on servers  104 , 105  with the DHCP/PXE proxy servers. In one embodiment of the invention, one or more target devices, such as devices  108 , 110 ,  112 , may include pre-boot extensions that allow the devices to download OS information from a boot server. 
     FIG. 2 is a block diagram of a data processing system in accordance with the present invention at  200 . In one embodiment of the invention, data processing system  200  may be implemented as one or more of the servers  104 , 105  shown in FIG.  1 . 
     Data processing system  200  may be a symmetric multiprocessors (SMP) system including a plurality of processors  202  and  204  connected to system bus  206 . Alternatively, a single processor system may be employed. Memory controller/cache  208  may also be connected to system bus  206 . Memory controller/cache  208  may provide an interface to local memory  209 . I/O bus bridge  210  may also be connected to system bus  206  and may provide an interface to I/O bus  212 . Memory controller/cache  208  and I/O bus bridge  210  may be integrated as depicted or may be separate compoents. 
     Peripheral component interconnect (PCI) bus bridge  214  connected to I/O bus  212  may provide an interface to PCI local bus  216 . One or more modems may be connected to PCI bus  216 . Typical PCI bus implementations will support four PCI expansion slots or add-in connectors. Modem  218  and network  220  may be connected to PCI local bus  216 . This connection may be through add-in boards. In one embodiment of the invention, modem  218  and accompanying connections provide communications links to target devices such as network computers. For example, such target devices may be those described above at FIG.  1 . 
     Additional PCI bus bridges  222  and  224  may provide interfaces for additional PCI buses  226  and  228 . Additional modems or network adapters may be supported from PCI buses  226  and  228 . In this manner, data processing system  200  may allow connections to multiple network computers. A memory-mapped graphics adapter  230  and hard disk  232  may also be connected to I/O bus  212  as depicted, either directly or indirectly. 
     The components depicted in FIG. 2 may be arranged as shown or in any suitable manner that allows data processing system  200  to function as desired. Additionally, other peripheral devices, such as optical disk drives and the like, may be used in addition to or in place of the components depicted. 
     One embodiment of data processing system  200  may be an IBM RISC/System 6000 system, a product of International Business Machines Corporation in Armonk, N.Y., running the Advanced Interactive Executive (AIX) operating system. 
     FIG. 3 is a block diagram of a data processing system in accordance with the present invention at  300 . Data processing system  300  may be, for example, one or more of the target devices  108 ,  110 ,  112  depicted in FIG.  1  and described above. In one embodiment of the invention, data processing system  300  may be a stand-alone system configured to be bootable without relying on a network communication interface. Alternatively, data processing system  300  may also comprise one or more network communication interfaces. Data processing system  300  may also be a personal digital assistant (PDA) device. Data processing system may also take the form of a notebook computer or handheld computer. Alternatively, data processing system  300  may be a kiosk or Web appliance. The processes of the present invention may also be applied to a multiprocessor data processing system. 
     Data processing system  300  may employ a peripheral component interconnect (PCI) local bus architecture. Although the depicted example employs a PIC bus, other bus architectures such as Accelerated Graphics Port (AGP) and Industry Standard Architecture (ISA) may be used. Processor  302  and main memory  304  may be connected to PCI local bus  306  via PCI bridge  308 . PCI bridge  308  may also include an integrated memory controller and cache memory for processor  302 . Additional connections to PCI local bus  306  may be made through direct component interconnection or through add-in boards. In one embodiment of the invention, local area network (LAN) adapter  310 , SCSI host bus adapter  312 , and expansion bus interface  314  are connected to PCI local bus  306  by direct component connection. In contrast, audio adapter  316 , graphics adapter  318  and audio/video adapter  319  are connected to PCI local bus  306  by add-in boards inserted into expansion slots. Expansion bus interface  314  may provide a connection for additional components such as, for example, a keyboard and mouse adapter  320 , a modem  322  and additional memory  324 . A small computer system interface (SCSI) host bus adapter  312  may provide a connection for additional components such as, for example, a hard disk drive  326 , a tape drive  328 , a CD-ROM drive  330  or a DVD  332 . PCI local bus  306  may be any suitable local bus implementation. Typical PCI local bus implementations will support three or four PCI expansion slots or add-in connectors. 
     In one embodiment of the invention, an operating system (OS) may run on processor  302 . This OS may be used to coordinate and provide control of various components within data processing system  300 . The OS may be a commercially available operating system. In one embodiment of the invention, the OS is Windows 2000, which is available from Microsoft Corporation. An object oriented programming system may be in communication with the OS and may run in conjunction with the OS. For example, the object-oriented programming system may provide calls to the OS from programs or applications executing on data processing system  300 . These programs or applications may be specific to the object-oriented programming system or may be programs or applications run by other programming systems. In one embodiment of the invention, the object-oriented programming system may be Java™, a trademark of Sun Microsystems, Inc. 
     Instructions for the OS, the object-oriented operating system, and applications or programs may be located on storage devices such as, for example, hard disk drive  326 . These operating systems, applications and/or programs may be loaded into main memory  304  for execution by processor  302 . 
     The components of system  300  depicted in FIG. 3 may be arranged as shown or in any suitable manner that allows data processing system  300  to function as desired. Other internal hardware or peripheral devices, such as flash ROM (or equivalent nonvolatile memory) or optical disk drives and the like, may be used in addition to or in place of the components depicted. For example, one embodiment of data processing system  300  may be configured with ROM and/or flash ROM in order to provide nonvolatile memory for storing operating system files and/or user-generated data. 
     FIG. 4 is a flow diagram of one embodiment of a method for selecting an operating system in accordance with the present invention at  400 . The operating system selected using this method may be an OS on a target device such as devices  108 ,  110 ,  112  depicted in FIG.  1  and described above. A user of a target device may login to the device before or after the process shown at  400  is completed. 
     At block  402 , the target device may send a DHCP broadcast. For example, the target device may be connected to a network and send the DHCP broadcast to the network and servers, such as BINL servers, in communication with the network. 
     At block  404 , the target device may receive DHCP/PXE proxy offers. These proxy offers may typically indicate which other components in communication with the target device are able to process a BINL request. 
     At block  406 , the target device may send a BINL request to a PXE proxy server. In one embodiment of the invention, this PXE proxy server is one of the proxy offers received at block  404 . 
     At block  408 , the target device may receive a BINL reply from the PXE proxy service. In one embodiment of the invention, this reply indicates the IP address of a BINL server. 
     At block  410 , the target device may send a TFTP request to the BINL server indicated at block  408 . In one embodiment of the invention, the request is for an initial NPB file. At block  412 , the reply may be received from the BINL server. For example, the server may provide an initial NBP file to the target device. 
     In one embodiment of the invention, the NBP file is a chained bootstrap. This chained bootstrap may be specified once as the default bootstrap. This chained bootstrap may be the first bootstrap loaded on the target device. This chained bootstrap “chains” itself, e.g., interposes itself in front of, the actual OS/bootstrap to be used on the target machine. In one embodiment of the invention, a reference to this chained bootstrap is the only entry in the BINL server. Alternatively, a reference to this chained bootstrap may be the default reply of the BINL server. Thus, the BINL configuration may not change regardless of the OS/bootstrap eventually used on a given target device. The BINL configuration also may not change when a new OS is added into the system. 
     At block  416 , further instructions may be received from administrative control of the server. These instructions may be based on information from the configuration file. Alternatively, the instructions may be written in a client-specific directory at the server (one per MAC address), and may contain location information for a name of a default operating system bootstrap. In one embodiment of the invention, the instructions in this client-specific directory are under administrative control. 
     These instructions may indicate which component of the system  200 ,  300  controls selection of the operating system. In one embodiment of the invention, the administrative instructions may indicate that a default OS and associated bootstrap are selected automatically. This default OS and associated bootstrap may be indicated by the target device or may be on the target device. This default OS and associated bootstrap may also be indicated by the server or may be on the server. 
     In another embodiment of the invention, these administrative instructions may indicate that the server will select an OS and associated bootstrap. This selection may be made, for example, by an administrator at the server. The server may select any available OS and associated bootstrap located in any suitable location such as, but not limited to, on the target device, on the server, or on a storage device in communication with the server. 
     In another embodiment of the invention, these administrative instructions may indicate an OS and associated bootstrap may be selected at the target device. This selection may be made, for example, by a user at the target device. The target device may select any available OS and associated bootstrap located in any suitable location such as, but not limited to, on the target device, on the server, or on a storage device in communication with the server. In one embodiment of the invention, the administrative instructions indicate that the server should send a list of available OS/bootstraps to the target device for selection. 
     The component of the system  200 ,  300  that selects the OS/bootstrap may differ depending on the circumstances indicated by the administrative instructions. For example, the instructions may indicate that in the mornings, all machines will automatically select OS/2 Warp 4™ to be loaded. Then, if a user logs in later in the day, the user may be allowed to select a different OS and associated bootstrap from a list. Then, the instructions may indicate that when a network administrator is working on the network, the selection of OS/bootstraps will be made by a network administrator. 
     FIG. 5 is a flow diagram of another embodiment of a method for selecting an operating system in accordance with the present invention at  500 . The operating system selected using this method may be an OS on a target device such as devices  108 ,  110 ,  112  depicted in FIG.  1  and described above. The process shown at  500  may be used once the process of FIG. 4 has been used, for example, to retrieve a chained bootstrap. A user of a target device may login to the device before or after the process shown at  500  is completed. 
     At block  518 , a default operating system and associated bootstrap may be received automatically at the target device. For example, the default operating system and associated bootstrap may have been discovered at block  414  and approved by administrative instructions at block  416 . The process may the proceed to block  550  where the chained bootstrap may then relocate itself so that it does not interfere with the default OS/bootstrap. In one embodiment, the chained bootstrap relocates itself in the memory of the target device. At block  552 , the default OS/bootstrap may be loaded on the target device. At block  554 , the default OS/bootstrap may be executed on the target device. 
     Alternatively, as seen at block  528 , the operating system and its associated bootstrap may have been decided administratively at block  416 . For example, an administrator at a server may determine which operating system will be sent to the target device. The process may then proceed to block  550  where the chained bootstrap may then relocate itself so that it does not interfere with the default OS/bootstrap. In one embodiment, the chained bootstrap relocates itself in the memory of the target device. At block  552 , the default OS/bootstrap may be loaded on the target device. At block  554 , the default OS/bootstrap may be executed on the target device. 
     Alternatively, the operating system and its associated bootstrap may be decided at the target device. For example, the administrative instructions at block  416  may indicate that the target device should select an operating system. As seen at block  538 , in one embodiment of the invention the target device receives a list of OS/bootstraps from which to select a preferred operating system. At block  540 , a preferred OS and associated bootstrap may be selected. At block  542 , the preferred operating system may be requested by the target device. This request may take the form of a TFTP request to the BINL server. At block  544 , the requested OS/bootstrap may be received. For example, the OS and its associated bootstrap may be downloaded to the target device. At block  550 , the chained bootstrap may then relocates itself so that it does not interfere with the preferred OS/bootstrap. In one embodiment, the chained bootstrap relocates itself in the memory of the target device. At block  552 , the preferred OS/bootstrap may be loaded on the target device. At block  554 , the preferred OS/bootstrap may be executed on the target device. 
     As described above, the selection of an OS and associated bootstrap may occur more than once at a given target device. Furthermore, an OS and associated bootstrap may be selected by one component in one instance, for example by the server or by an administrator at the server and then by another component in another instance, for example by the target device or a user at the target device. For example, when a user first logs on to a target device, the only OS/bootstrap available for selection may be a default selection of Windows 2000™. However, if the same target device is accessed by an administrator at the server, Linux and OS/2 Warp 4 may also be available for selection. Furthermore, communication between the same target device and the server may determine that when the same user logs on within certain parameters, (e.g. after the user has been through a software training program or after 5 p.m. on weekdays), the user may then receive other OS/bootstrap selections at the target device in addition to Windows 2000™. 
     While the present invention has been described in the context of a fully functioning data processing system, it will be appreciated that the processes described may be distributed in any other suitable context. For example, the processes described may take the form of a computer readable medium of instructions. The present invention applies equally regardless of the type of signal bearing media actually used to carry out the distribution. Examples of computer readable media include recordable-type medium, such as a floppy disk, a hard disk drive, a RAM, CD-ROMs, DVD-ROMS, and transmission-type media, such as digital and analog communications links, wired or wireless communications links using transmission forms such as, for example, radio frequency and light wave transmissions. The computer readable media may take the form of coded formats that are decoded for actual use in a particular data processing system. 
     While the embodiments of the invention disclosed herein are presently considered to be preferred, various changes and modifications can be made without departing from the spirit and scope of the invention. The scope of the invention is indicated in the appended claims, and all changes that come within the meaning and range of equivalents are intended to be embraced therein.