You can display and change the default boot device on a SUN Sparc server from the eeprom console.
List the bootable devices with the devalias command,
ok devalias
cdrom /pci@0,600000/pci@0/pci@0/scsi@0/disk@4,0:f
net /pci@0,600000/pci@0/pci@1/pci@0/network@4
disk /pci@0,600000/pci@0/pci@0/scsi@0/disk@0
name aliases
List the current boot device.
ok printenv boot-device
boot-device = disk
Change the boot device from disk to network.
ok setenv boot-device net
boot-device = net
Verify the change.
ok printenv boot-device
boot-device = net
Save the change.
ok reset-all
After the server rests, boot from he device
ok boot