I found my mistake !
I fact in configurations/server-config/Security/Realms you don't have to create a new Realms but to
change admin-realm to use a Directory Server and set it as default realm for the domain.
Then we you restart or connect to the DAS you have to give an administrator belong to your group in Directory Server.
Notice : In DAS , I have a HTTP 500 error when I clic on domain/Administrator password
Thanks for for help.
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