Oracle : Ошибка ORA-12668

"Dedicated server: outbound protocol does not support proxies"
*Cause: The protocol specified to perform an externally-identified proxy
connection (database link) from a dedicated server does
not support proxy connections.
*Action: Specify a protocol in the Oracle Net connect descriptor used for
the connection that does support externally-authenticated proxy
NOTE: Because of a limitation in Oracle Net, the protocol used for
the proxy connection must the same as that used for the
connection from the client to the server.

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