This is correct (though I think the function theoretically existed in Alpha, you may just not have found it). It's certainly possible in Beta, though there are one or two bugs.
Posted Nov 28, 2012 13:41 UTC (Wed) by Ben_P (guest, #74247)
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Thanks to both parent comments. IIRC the installer didn't give me the option to install to running and/or pre-configured softraid targets either. Can anyone confirm that's fixed in the beta?