System for automated boot from disk image
View Patent ↗A system allowing a target machine to be booted up from a disk image stored in memory. Instead of reading the boot-up information from a disk drive or other physical device the data is read from memory. No modification is necessary to native operating system, input/output subsystem, bootstrap code, etc., since the invention modifies characteristics, such as vectors used by the operating system, to make the disk image in memory appear to be the same as a standard external device.
1. A method comprising:
storing a boot image in a memory of a computer system, wherein
said storing comprises copying said boot image from a physical medium to said memory,
said computer system is coupled to said physical medium via a network, and
said copying comprises downloading said boot image from said physical medium to said memory via said network;
executing said boot image from said memory; and
causing a process executed by said computer system to initiate said executing,
wherein said causing comprises
modifying a vector in said computer system such that an attempt to access a physical storage unit results in said executing.
2. The method of claim 1 , further comprising:
in response to said copying, causing a process executed by said computer system to initiate said executing.
3. The method of claim 1 , further comprising:
changing a characteristic of said computer system, wherein said changing causes a process executed by said computer system to access said boot image.
4. The method of claim 3 , wherein
said changing causes said process executed by said computer system to access said boot image, if said process attempts to access a physical device.
5. The method of claim 4 , further comprising:
modifying a vector in said computer system such that an attempt to access a disk drive results in said executing said boot image.
6. The method of claim 4 , further comprising:
simulating a disk drive by modifying a vector in said computer system.
7. An apparatus comprising
a target computer, comprising
a first processor,
a memory coupled to said first processor,
a first computer readable medium coupled to said first processor, and
first computer code, encoded in said first computer readable medium, configured to cause said first processor to
store a boot image in said memory by virtue of being configured to cause said first processor to copy said boot image from a physical medium to said memory, wherein
said physical medium is coupled to said first processor via a network, and
said boot image is copied from said physical medium to said memory via said network;
execute said boot image from said memory; and
change a characteristic of said target computer, wherein said change causes a process executed by said target computer to initiate said first computer code configured to cause said first processor to execute said boot image from said memory.
8. The apparatus of claim 7 , wherein said first computer code is further configured to cause said processor to:
cause a process executed by said target computer to initiate said first computer code configured to cause said first processor to execute said boot image from said memory.
9. The apparatus of claim 7 , wherein said first computer code is further configured to cause said processor to:
in response to said first computer code configured to cause said processor to copy said boot image from said physical medium to said memory, cause a process executed by said target computer to initiate said first computer code configured to cause said first processor to execute said boot image from said memory.
10. The apparatus of claim 7 , wherein
said change causes said process executed by said target computer to access said boot image if said process attempts to access a physical device.
11. The apparatus of claim 7 , further comprising:
a server computer, coupled to said target computer and comprising
a second processor,
a second computer readable medium coupled to said second processor, wherein said second computer readable medium comprises said physical medium, and
second computer code, encoded in said second computer readable medium, configured to cause said second processor to download said boot image to said target computer.
12. The apparatus of claim 11 , wherein said second computer code configured to cause said second processor is further configured to:
cause said first processor to store said boot image in said memory and to execute said boot image from said memory.
13. The apparatus of claim 12 , further comprising:
a network, wherein
said target computer and said server computer are coupled to one another via said network, and
second computer code configured to cause said second processor to download said boot image to said target computer is further configured to cause said second processor to download said boot image to said target computer via said network.
14. A computer program product comprising:
a first set of instructions, executable on a computer system, configured to store a boot image in a memory of said computer system, wherein
said first set of instructions comprises a first subset of instructions, executable on
said computer system, configured to copy said boot image from a physical medium to said memory,
said computer system is coupled to said physical medium via a network, and
said first subset of instructions comprises a first sub-subset of instructions, executable on said computer system, configured to download said boot image from said physical medium to said memory via said network; and
a second set of instructions, executable on said computer system, configured to execute said boot image from said memory;
a third set of instructions, executable on said computer system, configured to change a characteristic of said computer system, wherein said third set of instructions cause a process executed by said computer system to execute said second set of instructions; and
computer readable media, wherein said computer program product is encoded in said computer readable media.
15. The computer program product of claim 14 , further comprising:
a fourth set of instructions, executable on said computer system, configured to cause a process executed by said computer system to initiate said second set of instructions.
16. The computer program product of claim 15 , further comprising:
a fifth set of instructions, executable on said computer system, configured to modify a vector in said computer system such that an attempt to access a physical storage unit results in said executing.
17. The computer program product of claim 14 , wherein
said fourth set of instructions cause said process executed by said computer system to access said boot image, if said process attempts to access a physical device.
18. A computer system comprising
a memory,
means for storing a boot image in said memory, wherein said means for storing is coupled to said memory, wherein
said means for storing comprises first means for copying said boot image from a physical medium to said memory,
said computer system is coupled to said physical medium via a network, and
said first means for copying comprises means for downloading said boot image from said physical medium to said memory via said network,
means for executing said boot image from said memory, wherein said means for executing said boot image is coupled to said memory, and
means for causing a process executed by said computer system to initialize said
means for executing wherein said means for causing comprises
means for modifying a vector in said computer system such that an attempt to access a physical storage unit results in said executing.
19. The computer system of claim 18 , further comprising:
a computer readable medium comprising said physical medium; and
second means for copying said boot image from said computer readable medium to said memory, wherein said second means for copying comprises said first means for copying.
20. The computer system of claim 19 , further comprising:
means for changing a characteristic of said computer system, wherein said means for changing is configured to cause a process executed by said computer system to initiate said boot image.
21. The computer system of claim 18 , further comprising:
means for causing a process executed by said computer system to initiate said executing, responsive to said first means for copying.
22. A computer system comprising:
a memory,
means for storing a boot image in said memory, wherein said means for storing is coupled to said memory, wherein
said means for storing comprises first means for copying said boot image from a physical medium to said memory,
said computer system is coupled to said physical medium via a network, and
said first means for copying comprises means for downloading said boot image from said physical medium to said memory via said network;
means for executing said boot image from said memory, wherein said means for executing said boot image is coupled to said memory; and
means for changing a characteristic of said computer system, wherein said changing causes a process executed by said computer system to access said boot image.
23. The computer system of claim 22 , wherein
said means for changing is configured to cause said process executed by said computer system to access said boot image, if said process attempts to access a physical device.
24. The computer system of claim 23 , further comprising:
means for modifying a vector in said computer system such that an attempt to access a disk drive results in said executing said boot image.
25. The computer system of claim 23 , further comprising:
means for simulating a disk drive comprising means for modifying a vector in said computer system.