Sun Microsystems Enterprise 250 Owner's Manual page 239

Note -
To boot the system over an Ethernet network, it is necessary that there be a
bootable image for Sun4u architecture somewhere on the network. For details, see
the installation instructions accompanying your Solaris software.
What to Do
1. At the ok prompt, enter either of the following commands:
a. To load the operating system into the server's volatile memory, enter:
ok boot net
Note - Because the operating system is only in volatile memory, it is not
retained across power cycles.
b. To install the operating system onto the server's internal system disk, enter:
ok boot net - install
Both commands boot the system, and the system console displays the system
prompt.
What Next
If you want to use the main logic board Ethernet interface as the default boot device,
you must change the value of certain OpenBoot parameters. For more information,
see OpenBoot 3.x Command Reference Manual in the Solaris System Administrator
AnswerBook for your specific Solaris release.
How to Boot the System Using a
PCI-Based Ethernet Interface
Before You Begin
Before you can boot the system over a network interface, you must complete the
installation procedure; see:
Administration and Networking
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