Before you begin
Trust between domains is established so that principals in a Subject from one WebLogic Server domain are accepted as principals in another domain. When this feature is enabled, identity is passed between WebLogic Server domains over an RMI connection without requiring authentication in the second domain. When inter-domain trust is enabled, transactions can commit across domains. A trust relationship is established when the Domain Credential for one domain matches the Domain Credential for another domain.
By default, the Domain Credential is randomly generated and therefor, no two domains will have the same Domain Credential. If you want two WebLogic Server domains to interoperate, you need to replace the generated credential with a credential you select, and set the same credential in each of the domains.
systemuser in the WebLogic Server 6.x Compatibility security domain.
After you finish
Perfom the same procedure in each domain for which you want to enable trust.