>> [booting from disk vs network]
> I probably forgot to mention that this should happen on remote
> control, with no console access.

Oh, yes, that does make a difference.

Doesn't "reboot" take a boot-command on sparc?  "reboot -- disk" or
"reboot -- net", in your case?

It seems to work for me - or at least "reboot -- netbsdN -s" did,
though I suspect it appended a space to the flags argument.

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