Activating FASTREBOOT to reduce the Solaris boot time

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The FastReboot feature of Oracle Solaris 11 implements an in-kernel boot loader that loads the kernel into memory and then switches to that kernel, so that the reboot process occurs within seconds. This feature is supported on both SPARC and x86 platforms.

On SPARC based platforms, Fast Reboot speeds up rebooting by skipping some POST tests.

On x86 based platforms, Fast Reboot bypasses firmware and the boot loader. The new kernel is loaded into memory by the running kernel, and control will be transferred to the newly loaded kernel.

For both SPARC and x86 platforms, The Fast Reboot feature is controlled by SMF and implemented through a boot configuration service, svc:/system/boot-config. The boot-config service provides a means for setting or changing the default boot parameters.

The fastreboot_default property of the boot-config service enables an automatic fast reboot of the system when either the reboot or the init 6 command is used. When the config/fastreboot_default property is set to true, the system automatically performs a fast reboot, without the need to use the reboot -f command.

By default, this property value is set to false on SPARC based systems, and true on an x86 based system.

The svc:/system/boot-config:default service consists of the following properties:

config/fastreboot_default
config/fastreboot_onpanic

These properties can be configured by using the svccfg and svcadm commands.

Examples

Example 1 — Enable Fast Reboot on a SPARC based system

The following example shows how to make a fast reboot the default behavior on a SPARC based system by setting the boot-config SMF service property to true.

# svccfg -s "system/boot-config:default" setprop config/fastreboot_default=true
# svcadm refresh svc:/system/boot-config:default

Setting the properties value to true accelerates the reboot process, which enables systems that support the Fast Reboot feature to bypass certain POST tests. When the property is set to true, you can perform a fast reboot of the system without having to use the -f option with the reboot command.

Example 2 — Disable Fast Reboot ONPANIC on a x86 based system

To disable the default behavior of the fastreboot_onpanic property on an x86 based system, you would set the properties value to false. For example:

# svccfg -s "system/boot-config:default" setprop config/fastreboot_onpanic=false
# svcadm refresh svc:/system/boot-config:default

NOTE: Changing one of the properties value does not affect the default behavior of the other property.

To reboot a system that has the Fast Reboot feature enabled, without reconfiguring the boot-config service to disable the feature, use the -p option with the reboot command. For example: 

# reboot -p