Every so ofter, on reboot, more usually after the machine has been off a while, but not always, the system boot with no network interface. So I init 0, do a show-nets and there is nothing. Also when Solaris is up fmadm faulty shows interface as faulty suggesting a mobo replacement - eek!
I can clear that, asr-clear at ok prompt and all is fine. Till next say one in five reboots and it's gone again. Same procedure clears it.
OBDIAG shows either 'net' as not there or there after asr-clear and tests fully with no errors.