Oracle Solaris ZFS Administration Guide

SPARC: Booting From a ZFS Root File System

On a SPARC based system with multiple ZFS BEs, you can boot from any BE by using the luactivate command.

During the Solaris OS installation and Oracle Solaris Live Upgrade process, the ZFS root file system is automatically designated with the bootfs property.

Multiple bootable datasets can exist within a pool. By default, the bootable dataset entry in the /pool-name/boot/menu.lst file is identified by the pool's bootfs property. However, a menu.lst entry can contain a bootfs command, which specifies an alternate dataset in the pool. In this way, the menu.lst file can contain entries for multiple root file systems within the pool.

When a system is installed with a ZFS root file system or migrated to a ZFS root file system, an entry similar to the following is added to the menu.lst file:

title zfsBE
bootfs rpool/ROOT/zfsBE
title zfs2BE
bootfs rpool/ROOT/zfs2BE

When a new BE is created, the menu.lst file is updated automatically.

On a SPARC based system, two new boot options are available:

Example 5–8 SPARC: Booting From a Specific ZFS Boot Environment

If you have multiple ZFS BEs in a ZFS storage pool on your system's boot device, you can use the luactivate command to specify a default BE.

For example, the following ZFS BEs are available as described by the lustatus output:

# lustatus
Boot Environment           Is       Active Active    Can    Copy      
Name                       Complete Now    On Reboot Delete Status    
-------------------------- -------- ------ --------- ------ ----------
zfsBE                      yes      no     no        yes    -         
zfs2BE                     yes      yes    yes       no     -

If you have multiple ZFS BEs on your SPARC based system, you can use the boot -L command to boot from a BE that is different from the default BE. However, a BE that is booted from a boot -L session is not reset as the default BE nor is the bootfs property updated. If you want to make the BE booted from a boot -L session the default BE, then you must activate it with the luactivate command.

For example:

ok boot -L
Rebooting with command: boot -L
Boot device: /pci@7c0/pci@0/pci@1/pci@0,2/LSILogic,sas@2/disk@0  File and args: -L

1 zfsBE
2 zfs2BE
Select environment to boot: [ 1 - 2 ]: 1
To boot the selected entry, invoke:
boot [<root-device>] -Z rpool/ROOT/zfsBE

Program terminated
ok boot -Z rpool/ROOT/zfsBE

Example 5–9 SPARC: Booting a ZFS File System in Failsafe Mode

On a SPARC based system, you can boot from the failsafe archive located in /platform/`uname -i`/failsafe as follows:

ok boot -F failsafe

To boot a failsafe archive from a particular ZFS bootable dataset, use syntax similar to the following:

ok boot -Z rpool/ROOT/zfsBE -F failsafe