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One of the slowest and most annoying aspects of system management is the simple act of rebooting the system. The sysadmin starts from a known state -- the OS is running -- and hands the computer over to an untrustworthy piece of software. With enough nodes involved, there is a good chance that the process will fail on one of them. Bootstrapping is well named -- it takes the system down to a low level, from which return is uncertain. It would be much better if we could use the known, trusted OS software to manage the boot process. The OS can apply all its power to the problem of locating, verfying, and loading a new OS image. Error checking and feedback can be far more robust. All that is needed is the OS software to make this possible. In this paper, we discuss five systems for Linux and Plan 9 that allow the OS to boot the OS. These systems allow for the complete elimination of old-fashioned boostraps. We also discuss our use of this technology in several different clusters, ranging from 1408 K8 nodes to 1024 P4 nodes to a 9-node Plan 9 cluster.