Abstract:
Disclosed are techniques for using known update technologies to automatically identify the updates installed on a physical machine prior to facsimile creation, to locate the update packages from an update server, and to download them to the machine performing the facsimile creation. The use of update technologies enables precise identification of the updates that affect the defined set of files requiring replacement, and thus minimizes the number of updates that need to be downloaded. In addition, the desired set of replacement files are extracted and cached to allow for their reuse during subsequent facsimile creations using either the same or different physical or virtual machine as the source. Downloading the minimal set of updates and caching them for reuse eliminates the redundant downloads of updates and results in a shorter time for facsimile creation.

Description:
BACKGROUND 
       [0001]    Physical and virtual machines over their lifetime have their operating systems and applications periodically upgraded by the installation of patches and updates. Examples of such patches and updates include, but are not limited to, service packs, hot fixes, fixes for security issues, and fixes for bugs in the installed versions of the software. Such updates sometimes affect the files in the defined set that need to be replaced during the creation of a virtual machine facsimile of the physical machine. Consequently, it may be critical to identify the updates that affected each file in the defined set of files in order to locate the correct version of the corresponding replacement file. 
         [0002]    Once the relevant set of updates has been identified, the updates need to be downloaded from a repository of updates and examined to locate the replacement files. The appropriate replacement files need to be copied onto the virtual machine facsimile. Such a download and replacement process needs to be performed during every virtual machine facsimile creation. 
         [0003]    Current solutions for the replacement problem typically address it using a manual process to identify and download the relevant updates, and by building customized scripts to find and replace the affected files in the facsimile. Such a process requires a trial and error approach, as well as user intervention, to keep the scripts current as new updates are released for the operating system and the applications. This can be a tedious and repetitive task as new updates may be released frequently. Changing the replacement scripts often imposes an additional test burden to ensure that they continue to operate correctly. 
       SUMMARY 
       [0004]    Existing update technologies may be employed to automatically identify the updates installed on a physical machine prior to facsimile creation, to locate the update packages from an update server, and to download them to the machine performing the facsimile creation. The use of such update technologies enables precise identification of the updates that affect the defined set of files requiring replacement, and thus may minimize the number of updates that need to be downloaded. Additionally, the desired set of replacement files may be extracted and cached to allow for their reuse during subsequent facsimile creations using either the same or a different physical or virtual machine as the source. Downloading a minimal set of updates and caching them for reuse may eliminate redundant downloads of updates and may result in a shorter time for facsimile creation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a flowchart of a process for creating a virtual machine facsimile. 
           [0006]      FIG. 2  depicts an example update manager system. 
           [0007]      FIG. 3  is a flowchart of a process for using update technologies to determine whether the updates or patches installed on a source machine need to be replaced during facsimile creation. 
           [0008]      FIG. 4  is a flowchart of a process for storing extracted replacement files in a cache to be reused during future facsimile creation. 
           [0009]      FIG. 5  is a block diagram of an example computing environment in which example embodiments and aspects may be implemented. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]      FIG. 1  is a flowchart of a process  10  for creating a virtual machine facsimile. A virtual machine facsimile may be created from a “source,” which may be a physical machine, a virtual machine that is currently running, or a pre-existing image (e.g., a virtual machine that is not currently running or a backup of a machine). 
         [0011]    At  12 , the source may be examined to ascertain its hardware and software profiles. As used herein, the term “profile” may refer to a set of hardware and/or software characteristics. For example, the source may be examined to determine the version of the operating system installed on it, as well as the versions of any system or application software installed on it. The source may be examined to identify any software patches or updates that may have been installed. The source hardware may be examined to determine how much memory and processing power (a.k.a., “CPU”) the source has, how many network cards it has, what networks it may be connected to, the number, types, and sizes of disks it has, etc. 
         [0012]    If the source is a pre-existing image, then the source may be represented by files on a data storage medium, rather than a running machine. Accordingly, the virtual machine configuration may be examined to ascertain the hardware and software profiles. 
         [0013]    If the source is a physical machine or a virtual machine that is currently running, then the physical machine may be examined to ascertain its hardware and software profiles. As part of examining the source, at  12 , update technologies may be employed to detect updates that may be currently installed on the physical or virtual machine for which the facsimile is being created. As used herein, the term “updates” includes software patches. The term “update technologies” refers to the use of an “update manager” for version control of certain “managed” software components. 
         [0014]      FIG. 2  depicts an example update manager system  20 . The update client  21  accesses the machine  22  that includes the managed software  23 , i.e., the software the version of which the update manager  20  endeavors to keep current. Typically, the update client  21  will reside and run on the machine  22  on which the managed software  23  is installed. 
         [0015]    The update server  24  keeps track of the most current versions of any number of managed software components  25 . The update server  24  is typically remote from the machine  22  on which the managed software  23  resides (i.e., the client machine). The update server  24  and the client machine  22  are typically interconnected via a network  26 , such as the Internet. Examples of such an update server may include a Windows Update Server (WSUS) or a Microsoft Systems Management Server (SMS). 
         [0016]      FIG. 3  depicts a method  30  for using update technologies to detect updates as part of examining a source (at  12  in  FIG. 1 ). As shown in  FIG. 3 , an update client may be employed to examine the source to determine which versions of certain managed components the source includes. So that it may “know” which components are managed components, the update client may, at  31 , maintain a list of managed components. Any or all of the software components residing on a source may be managed components. 
         [0017]    At  32 , the update client may examine the source to determine which version of each managed component the source currently includes. At  33 , the update client may store (e.g., in memory on the source machine) the list of managed components and a version associated with each. 
         [0018]    At  34 , the update client may examine the source to determine whether any updates have been applied to any of the managed components. If so, at  35 , the update client may store an update identifier (e.g., version number) associated with the update and the managed component to which the update was applied. 
         [0019]    Thus, an update client may be employed to examine the source to identify the most-current versions of certain managed software components installed on the source, including the most-current versions of any updates (including patches) that may be installed on the source. As will be described below, the use of update technologies to identify the updates currently installed on the source may reduce the number of files that need to be downloaded to make the captured image bootable. 
         [0020]    Description of a process for creating a virtual machine facsimile now continues with reference once again to  FIG. 1 . After the source is examined at  12 , the source may be “imaged.” How the source is imaged may depend on whether the source, itself, is an image. An “image” may be considered a set of files that replicate the contents (e.g., the hardware and software profiles) of a physical machine. 
         [0021]    If, at  14 , it is determined that the source is an image, then, at  22 , the source may be imaged by reading the set of files that form the image, and converting the format of any such files, if necessary, to generate a set of files in a desired file format. 
         [0022]    If, at  14 , it is determined that the source is not merely an image, and, therefore that the source is either a physical machine or a virtual machine that is currently running, then, at  16 , the physical machine may be imaged. In this case, where the machine to be imaged is a virtual machine that is currently running, the term “physical machine to be imaged” may refer to the physical machine that the virtual machine emulates. Techniques for imaging a physical machine are well-known. Examples of such techniques are described and claimed in U.S. patent application Ser. No. 11/430,676, filed May 8, 2006, the disclosure of which is hereby incorporated herein by reference. 
         [0023]    At  18 , the captured image may be made “bootable.” That is, the image captured at  14  or  22  may be made compatible with the configuration emulated by the virtual server software that will be used to “run” the facsimile. 
         [0024]      FIG. 4  is a flowchart of an example process  40  for making a captured image bootable. At  41 , the minimal list of updates (identified at  12  in  FIG. 1 ) may be downloaded from the update server to the machine performing the facsimile creation process. Update technologies may be used to query, locate, and download the list of updates. 
         [0025]    The updates may be examined, at  42 , to extract appropriate replacement files for each of the files that need to be replaced or added. These files may then be used to perform the replacement and render the virtual machine facsimile operational. It should be understood, of course, that existing files may be replaced, or new files added/installed (e.g., drivers for emulated devices). At  43 , the extracted replacement files may be stored in a cache on the machine performing the facsimile creation process to be reused during future facsimile creation. This is an optimization that tends to ensure that each update is downloaded only once. Once all the required updates have been added to the cache, future facsimile creations can proceed without requiring any downloads. 
         [0026]    With reference again to  FIG. 1 , the virtual machine may be created and configured at  20 . That is, the hard disks defined by the file set that forms the captured image may be logically assembled to form the virtual machine. The hard disks may be logically connected to one another, and the virtual machine may be started running. Thus, software and operating system update technologies may be employed for the process of creating a virtual machine facsimile of an existing physical or virtual machine. 
       Exemplary Computing Arrangement 
       [0027]      FIG. 5  shows an exemplary computing environment in which example embodiments and aspects may be implemented. The computing system environment  100  is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality. Neither should the computing environment  100  be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary operating environment  100 . 
         [0028]    Numerous other general purpose or special purpose computing system environments or configurations may be used. Examples of well known computing systems, environments, and/or configurations that may be suitable for use include, but are not limited to, personal computers, server computers, hand-held or laptop devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, embedded systems, distributed computing environments that include any of the above systems or devices, and the like. 
         [0029]    Computer-executable instructions, such as program modules, being executed by a computer may be used. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Distributed computing environments may be used where tasks are performed by remote processing devices that are linked through a communications network or other data transmission medium. In a distributed computing environment, program modules and other data may be located in both local and remote computer storage media including memory storage devices. 
         [0030]    With reference to  FIG. 5 , an exemplary system includes a general purpose computing device in the form of a computer  110 . Components of computer  110  may include, but are not limited to, a processing unit  120 , a system memory  130 , and a system bus  121  that couples various system components including the system memory to the processing unit  120 . The processing unit  120  may represent multiple logical processing units such as those supported on a multi-threaded processor. The system bus  121  may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus (also known as Mezzanine bus). The system bus  121  may also be implemented as a point-to-point connection, switching fabric, or the like, among the communicating devices. 
         [0031]    Computer  110  typically includes a variety of computer readable media. Computer readable media can be any available media that can be accessed by computer  110  and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media includes both 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. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CDROM, digital versatile disks (DVD) or other optical disk 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 accessed by computer  110 . Communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. 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. Combinations of any of the above should also be included within the scope of computer readable media. 
         [0032]    The system memory  130  includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM)  131  and random access memory (RAM)  132 . A basic input/output system  133  (BIOS), containing the basic routines that help to transfer information between elements within computer  110 , such as during start-up, is typically stored in ROM  131 . RAM  132  typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit  120 . By way of example, and not limitation,  FIG. 5  illustrates operating system  134 , application programs  135 , other program modules  136 , and program data  137 . 
         [0033]    The computer  110  may also include other removable/non-removable, volatile/nonvolatile computer storage media. By way of example only,  FIG. 5  illustrates a hard disk drive  140  that reads from or writes to non-removable, nonvolatile magnetic media, a magnetic disk drive  151  that reads from or writes to a removable, nonvolatile magnetic disk  152 , and an optical disk drive  155  that reads from or writes to a removable, nonvolatile optical disk  156 , such as a CD ROM or other optical media. Other removable/non-removable, volatile/nonvolatile computer storage media that can be used in the exemplary operating environment include, but are not limited to, magnetic tape cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM, solid state ROM, and the like. The hard disk drive  141  is typically connected to the system bus  121  through a non-removable memory interface such as interface  140 , and magnetic disk drive  151  and optical disk drive  155  are typically connected to the system bus  121  by a removable memory interface, such as interface  150 . 
         [0034]    The drives and their associated computer storage media discussed above and illustrated in  FIG. 5 , provide storage of computer readable instructions, data structures, program modules and other data for the computer  110 . In  FIG. 5 , for example, hard disk drive  141  is illustrated as storing operating system  144 , application programs  145 , other program modules  146 , and program data  147 . Note that these components can either be the same as or different from operating system  134 , application programs  135 , other program modules  136 , and program data  137 . Operating system  144 , application programs  145 , other program modules  146 , and program data  147  are given different numbers here to illustrate that, at a minimum, they are different copies. A user may enter commands and information into the computer  20  through input devices such as a keyboard  162  and pointing device  161 , commonly referred to as a mouse, trackball or touch pad. Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit  120  through a user input interface  160  that is coupled to the system bus, but may be connected by other interface and bus structures, such as a parallel port, game port or a universal serial bus (USB). A monitor  191  or other type of display device is also connected to the system bus  121  via an interface, such as a video interface  190 . In addition to the monitor, computers may also include other peripheral output devices such as speakers  197  and printer  196 , which may be connected through an output peripheral interface  195 . 
         [0035]    The computer  110  may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer  180 . The remote computer  180  may be a personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computer  110 , although only a memory storage device  181  has been illustrated in  FIG. 5 . The logical connections depicted in  FIG. 5  include a local area network (LAN)  171  and a wide area network (WAN)  173 , but may also include other networks. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet. 
         [0036]    When used in a LAN networking environment, the computer  110  is connected to the LAN  171  through a network interface or adapter  170 . When used in a WAN networking environment, the computer  110  typically includes a modem  172  or other means for establishing communications over the WAN  173 , such as the Internet. The modem  172 , which may be internal or external, may be connected to the system bus  121  via the user input interface  160 , or other appropriate mechanism. In a networked environment, program modules depicted relative to the computer  110 , or portions thereof, may be stored in the remote memory storage device. By way of example, and not limitation,  FIG. 5  illustrates remote application programs  185  as residing on memory device  181 . It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used. 
         [0037]    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.