Following some experimentation, i've concluded as follows. There are two "asadmin" scripts installed: the default one in "/usr/bin/asadmin", and another one in "/usr/share/sunappserver/bin". The former works, by default, with the "~/glassfish" directory and the domains therein, while the latter works, by default, with the "/var/lib/sunappserver" directory and the domains therein.
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