Can I eliminate reboots with kexec?
Installing operating systems often times requires a reboot of the Machine several times. For physical (aka bare) metal, this reboot cycle can add many minutes (often times 10 or more minutes) to the installation process.
When installing Linux operating systems, it may be possible to utilize the Linux Kernel kexec mechanism to "exec" in to the new Kernel environment without requiring the Machine to pass through a full POST cycle.
Solution¶
Setting the [kexec-ok]{.title-ref} param to [true]{.title-ref} on the [global]{.title-ref} or machine specific profile allows BootEnvs that are kexec enabled to skip rebooting when changing to that BootEnv. For example, Sledgehammer enables kexec and can be started without a reboot from Linux environments.
This is a Linux specific feature.
Note
The kexec capability is defined by the compiled Linux Kernel configuration. Some Linux distributions do not enable kexec by default. In these cases, you may have to compile a custom kernel version with kexec enabled. In addition, not all transition states can successfully utilize kexec even if it is enabled in the kernel.
Additional Information¶
Additional resources and information related to this Knowledge Base article.
See Also¶
Versions¶
Enabled in the v3.x versions and newer.
Keywords¶
sledgehammer, kexec, post, reboot