I think they actually want the opposite. this is referencded by bugid#198490 where anaconda is too aggressive in it's search. they would like it to just see local storage and disregard any SAN attached lun's. they're using a filesystem that anaconda doesn't recognize which is giving them the above message.
Although this bugzilla was approved for RHEL 4.5, we were unable to resolve it in time to be included in the release. Therefore it is now proposed for RHEL 4.6.
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
*** Bug 242161 has been marked as a duplicate of this bug. ***
Added the ignoredisk --only-use option. Please give this thorough testing in the nightly trees and the beta.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2007-0816.html