# US 8,752,039 B1 · Dynamic upgrade of operating system in a network device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,752,039 B1 - Document ID: US8752039B1 - Status: Granted - Kind: B1 - Application number: 12/543,940 - Filed: 2009-08-19 - Granted: 2014-06-10 - Earliest claimed: 2009-08-19 - Assignees: Juniper Networks, Inc. - Applicants: Vinay Bapat - Inventors: Vinay Bapat - Web page: https://patentgrep.com/patent/US8752039B1 ## CPC - G06F 8/65: Updates (security arrangements therefor G06F21/57) - G06F 8/63: {Image based installation; Cloning; Build to order} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract An upgrade procedure may be executed at a network device to allow the network device to automatically upgrade an operating system to a new operating system. The upgrade procedure may include receiving a bootable image file of an upgrade operating system that is different from an operating system being run by the network device and which uses a file system format that is different from the file system format of the operating system being run by the network device. The bootable image file includes a binary file format that conforms to the file system format used by the upgrade operating system. The network device allocates contiguous space on a drive of the network device and copies the bootable image file to the contiguous space. The network device also modifies a master boot record of the drive such that the contiguous space on the drive is reflected in the master boot record as a bootable partition of the drive. ## Claims ### Claim 1 A method comprising: receiving, by a network device, a bootable image file of a first operating system that is different from a second operating system being run by the network device, a first file system format of the first operating system being different from a second file system format of the second operating system, and the bootable image file including a binary file format that conforms to the first file system format; allocating, by the network device, contiguous space on a drive of the network device, the contiguous space having a size at least equal to a size of the bootable image file, and the drive being formatted according to the second file system format; copying, by the network device, the bootable image file to the contiguous space on the drive of the network device; modifying, by the network device, a master boot record of the drive of the network device to indicate, in the master boot record, that the contiguous space on the drive of the network device is a bootable partition of the drive of the network device; placing, by the network device, hardware of the network device into a pass-through mode that allows traffic to pass through the network device without direction from the second operating system; and causing, by the network device, the network device to reboot to load the first operating system. ### Claim 2 (depends on 1) The method of claim 1, further comprising: creating one or more new partitions on the drive of the network device; and reformatting the one or more new partitions to use the first file system format of the first operating system. ### Claim 3 (depends on 2) The method of claim 2, further comprising: installing the first operating system in the one or more new partitions. ### Claim 4 (depends on 2) The method of claim 2, further comprising: updating the master boot record to reflect the one or more new partitions. ### Claim 5 (depends on 1) The method of claim 1, where the hardware includes a wide area network (WAN) accelerator. ### Claim 6 (depends on 1) The method of claim 1, where allocating the contiguous space on the drive of the network device includes: allocating the contiguous space to be aligned with a sector boundary of the drive of the network device. ### Claim 7 (depends on 1) The method of claim 1, further comprising: saving a backup of the master boot record before modifying the master boot record. ### Claim 8 (depends on 1) The method of claim 1, where the first operating system includes a linux-based operating system. ### Claim 9 (depends on 1) The method of claim 1, where allocating the contiguous space includes: using software tools available through the second operating system to allocate the contiguous space. ### Claim 10 (depends on 9) The method of claim 9, further comprising: using, after causing the network device to reboot, other software tools available through the first operating system to complete an upgrade to the first operating system. ### Claim 11 A non-transitory computer-readable medium storing instructions, the instructions comprising: one or more instructions that, when executed by at least one processor of a network device, cause the at least one processor to: receive a bootable image file of a first operating system that is different from a second operating system being run by the network device, a first file system format used by the first operating system being different from a second file system format used by the second operating system, and the bootable image file including a binary file format that conforms to the first file system format; allocate contiguous space on a drive of the network device, the contiguous space having a size at least equal to a size of the bootable image file, and the drive being formatted according to the second file system format; copy the bootable image file to the contiguous space on the drive of the network device; modify a master boot record of the drive of the network device to indicate, in the master boot record, that the contiguous space on the drive of the network device is a bootable partition of the drive of the network device; place hardware of the network device into a pass-through mode that allows traffic to pass through the network device without direction from the second operating system; and cause the network device to load the first operating system based on the master boot record. ### Claim 12 (depends on 11) The non-transitory computer-readable medium of claim 11, where the instructions further comprise: one or more instructions that, when executed by the at least one processor of the network device, cause the at least one processor to: create one or more new partitions on the drive of the network device; and reformat the one or more new partitions to use the first file system format. ### Claim 13 (depends on 12) The non-transitory computer-readable medium of claim 12, where the instructions further comprise: one or more instructions that, when executed by the at least one processor of the network device, cause the at least one processor to: install the first operating system in the one or more new partitions. ### Claim 14 (depends on 12) The non-transitory computer-readable medium of claim 12, where the instructions further comprise: one or more instructions that, when executed by the at least one processor of the network device, cause the at least one processor to: update the master boot record to reflect the one or more new partitions. ### Claim 15 (depends on 11) The non-transitory computer-readable medium of claim 11, where the hardware includes a wide area network (WAN) accelerator. ### Claim 16 (depends on 11) The non-transitory computer-readable medium of claim 11, where the one or more instructions to allocate the contiguous space on the drive of the network device include: one or more instructions that, when executed by the at least one processor of the network device, cause the at least one processor to: allocate the contiguous space to be aligned with a sector boundary of the drive of the network device. ### Claim 17 A network device comprising: one or more processors to: receive a bootable image file of a first operating system that is different from a second operating system being run by the network device, a first file system format of the first operating system being different from a second file system format of the second operating system; copy the bootable image file to a contiguous space on a drive of the network device; modify a master boot record of the drive of the network device to indicate, in the master boot record, that the contiguous space on the drive of the network device is a bootable partition of the drive of the network device; place the network device into a pass-through mode that allows traffic to pass through the network device during loading of the first operating system; and reboot the network device to load the first operating system based on the master boot record. ### Claim 18 (depends on 17) The network device of claim 17, where the bootable image file includes a binary file format that conforms to the first file system format. ### Claim 19 (depends on 17) The network device of claim 17, where the network device includes a wide area network (WAN) accelerator. ### Claim 20 (depends on 17) The network device of claim 17, where the one or more processors are further to: create one or more new partitions on the drive of the network device; and reformat the one or more new partitions to use the first file system format. ### Claim 21 (depends on 20) The network device of claim 20, where the one or more processors are further to: install the first operating system in the one or more new partitions. ### Claim 22 (depends on 20) The network device of claim 20, where the one or more processors are further to: update the master boot record to reflect the one or more new partitions.