The newest update of Solaris 10 (09/10) brings a new feature called autoregistration. This can be automated using the new "auto_reg" option in the sysidcfg file. Or rather, it can be sometimes. Due to a (already known) bug, this new parameter is ignored by the GUI-installer, which will query you for the registration details no matter what you put in the sysidcfg file. The GUI-installer usually runs if you have a screen (and video card) attached to the system. On headless servers, the text-installer runs, which correctly acts upon "auto_reg" settings.

As a workaround for workstations, use "boot net - install nowin" instead of the usual "boot net - install", and you're all set.

Many thanks to Peter Tribble, who suffered through this and eventually found the solution for me.

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