Sun Fire 480R boot questions

I have two boot related questions on a Sun Fire 480R.
(1)	When type ok> boot  or from O/S # shutdown bI 6, it always boot from
network.
(2)	It always performs full diagnose on boot.
Here is printenv:
Variable Name           Value                          Default Value
test-args
diag-passes             0                              1
keyboard-layout         US-English
local-mac-address?      true                           false
scsi-initiator-id       7                              7
oem-logo                                               No default
oem-logo?               false                          false
oem-banner                                             No default
oem-banner?             false                          false
ansi-terminal?          true                           true
screen-#columns         80                             80
screen-#rows            34                             34
ttya-rts-dtr-off        false                          false
ttya-ignore-cd          true                           true
ttya-mode               9600,8,n,1,-                   9600,8,n,1,-
output-device           ttya                           ttya
input-device            ttya                           ttya
auto-boot-on-error?     true                           true
load-base               16384                          16384
auto-boot?              true                           true
network-boot-arguments
boot-command            boot                           boot
diag-file
diag-device             net                            net
boot-file
boot-device           disk0
/pci@9,600000/SUNW,qlc@2/fp@0,0/disk@w21000014c34daf7f,0:a net
disk net
use-nvramrc?            false                          false
nvramrc
security-mode           none                           No default
security-password                                      No default
security-#badlogins     0                              No default
verbosity               normal                         normal
fcode-debug?            false                          false
diag-out-console        false                          false
diag-trigger            error-reset power-on-res ...   error-reset
power-on-res ...
service-mode?           false                          false
diag-script             normal                         normal
diag-level              min                            max
diag-switch?            false                          false
error-reset-recovery    sync                           sync
{3} ok devalias
disk1                    /pci@9,600000/SUNW,qlc@2/fp@0,0/disk@1,0
disk0                    /pci@9,600000/SUNW,qlc@2/fp@0,0/disk@0,0
{3} ok boot
Resetting ...
Rebooting with command: boot
Boot device: net  File and args:
b&
rsc> showsc
RSC Version: 2.2.3
RSC Bootmon version: 2.0.0
RSC Firmware version: 2.2.3

Thanks.
Warren