If the root disk is encapsulated and mirrored, you can use one of its mirrors to boot the system if the primary boot disk fails.
On a Solaris SPARC system, booting from an alternate boot disk requires that some EEPROM settings are changed.
A Solaris SPARCŪ system prompts for a boot command unless the autoboot flag has been set in the nonvolatile storage area used by the firmware. Machines with older PROMs have different prompts than that for the newer V2 and V3 versions. These newer versions of PROM are also known as OpenBoot PROMs (OBP). The boot command syntax for the newer types of PROMs is:
ok boot [OBP names] [filename] [boot-flags]
The OBP names specify the OpenBoot PROM designations. For example, on Desktop SPARC systems, the designation sbus/esp@0,800000/sd@3,0:a indicates a SCSI disk (sd) at target 3, lun 0 on the SCSI bus, with the esp host bus adapter plugged into slot 0.
You can use Veritas Volume Manager boot disk alias names instead of OBP names. Example aliases are vx-rootdisk or vx-disk01. To list the available boot devices, use the devalias command at the OpenBoot prompt.
The filename argument is the name of a file that contains the kernel. The default is /kernel/unix in the root partition. If necessary, you can specify another program (such as /stand/diag) by specifying the -a flag. (Some versions of the firmware allow the default filename to be saved in the nonvolatile storage area of the system.)
Boot flags are not interpreted by the boot program. The boot program passes all boot-flags to the file identified by filename.
See the kadb (1M) manual page.
See the kernel (1) manual page.