Oracle Names and Hierarchical Domains

Is it possible to make Oracle Names use DDO with hierarchical domains?

Would like to create remote/delegated admin regions with DDO within their own domains and reference remote names servers as the corporate centralized ones as the navigation path to navigate between domains.

Do you have to define every names server on every other one? What happens internally when the repository isn't available to the names server? What impact does the checkpointing and caching parms have on this and on performance?

Manuals says no but seems like the only time you'd want to use DDO is with complex architectures with multiple names servers.

Would be very interested in talking with anyone who's also involved with setting up large corporate names server architecture.

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Gary Melhaff
Senior Database Analyst
Weyerhauser Corporation