Likewise Open is an application that joins Linux, Unix, and Mac OS machines to Microsoft Active Directory and securely authenticates users with their domain credentials. Features include: joining non-Windows systems to Active Directory domains in a single step from the command line or from a GUI; authenticating users with a single user name and password; enforcing the same password policies for all platforms; supporting multiple forests with one-way and two-way cross forest trusts; caching credentials in case your domain controller goes down; and providing single sign-on for SSH and Putty. It does not require Active Directory schema changes for installation.
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