The Oracle OpenBoot 4.x Administration Guide[0] documents a few useful
options for network boot.
Basically do either
{ok} setenv network-boot-arguments tftp-retries=0
{ok} boot net ...
or
{ok} boot net:tftp-retries=0 ...
Newer machines like the T4-2 using OpenBoot 4.38.16 also support
BOOTP/DHCP besides RARP; "dhcp,hostname=puffy" works as expected on my
T4-2, but "boot-filename" and "boot-retries" remain unsupported on this
particular machine despite being documented in the guide.
0: https://docs.oracle.com/cd/E63648_01/html/E63649/gpvll.html#scrolltoc
Feedback? OK?
Index: eeprom.8
===================================================================
RCS file: /cvs/src/usr.sbin/eeprom/eeprom.8,v
retrieving revision 1.22
diff -u -p -r1.22 eeprom.8
--- eeprom.8 8 Jan 2020 14:45:36 -0000 1.22
+++ eeprom.8 6 Oct 2022 09:40:45 -0000
@@ -197,7 +197,7 @@ one is likely to see on a system with an
NOTE: this list
may be incomplete or incorrect due to differences between revisions
of the OpenPROM.
-.Bl -tag -width "last-hardware-update "
+.Bl -tag -width "network-boot-arguments "
.It Ar sunmon-compat?
If true, the old EEPROM-style interface will be used while in the monitor,
rather than the OpenPROM-style interface.
@@ -298,6 +298,8 @@ or
specifying the default console output device.
.It Ar keyboard-click?
If true, the keys click annoyingly.
+.It Ar network-boot-arguments
+Comma separated list of arguments for booting over RARP or BOOTP/DHCP and TFTP.
.It Ar sd-targets
A string in the format
.Dq 31204567
