It's tested only with Indy, I don't know if it works with other SGI models.
You can check your compleat ID from the sticker of backside near to power supply, it's someone similar to 080069123456. ( this is only for use your unique real addr ID ).
080069... is the same for all SGI, only change the last 6 numbers, now go to PROM monitor an type:
replace aa, bb, cc, dd, ee, ff for your ID.
fill -w -v 0xaa 0xbfbe04e8
fill -w -v 0xbb 0xbfbe04ec
fill -w -v 0xcc 0xbfbe04f0
fill -w -v 0xdd 0xbfbe04f4
fill -w -v 0xee 0xbfbe04f8
fill -w -v 0xff 0xbfbe04fc
Example for 080069123456
After type this commands reset your INDY and enjoy.
For the Indy it changes the value in NVRAM, i.e. it should stay after reboot (though I have only tested with MAME) [edit: seems it was meant to be write protected, unsure if MAME enforces this]. It seems the possibility to change the sysid at all was due to some kind of bug which could overwrite it.
For the later systems the "feature" to change sysid was disabled, but it seems to work for the O2, however the sysid does not stick between reboots. According to some old newsgroup posts from a SGI employee, it was not intended to work with the O2 - it's a bug that it works at all...
| On the O2 systems, you can use
| setenv -f eaddr 08:00:69:xx:xx:xx
| and then just boot the system. it will stay with that eaddr as long as it's
| not powered off.
| i have tried this and it works.
It's a bug that it works...
For the original requestor, there is no such command, at least
for the systems that use the nvram eaddr as the basis for the
licensing serial number (the desktop machines, and some of the
servers). And no, I'm not just saying the party line; there really
isn't such a command.