When attempting to bind a client to Open Directory, a client may receive an alert that the computer already exists. Looking up the computer in Open Directory may return a duplicate "LDKC:SHA1" entry. This may occur when a system is installed from a NetInstall image that was created after the point in the Mac OS X install where the com.apple.kerberos.kdc certificate had been created; so each new imaged system has the same certificate and LKDC:SHA1 hash.
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