Описание ошибки Oracle : ORA-28547
28547, 0000, "connection to server failed, probable Oracle Net admin error"
*Cause: A failure occurred during initialization of a network connection
from a client process to the Oracle server. The connection
was completed but a disconnect occurred while trying to
perform protocol-specific initialization, usually due to
use of different network protocols by opposite sides
of the connection. This usually is caused by incorrect
Oracle Net administrative setup for database links or external
procedure calls. The most frequent specific causes are:
-- The connection uses a connect string which refers
to a Heterogeneous Services agent instead of
an Oracle server.
-- The connection uses a connect string which includes
an (HS=) specification.
-- Hitting Ctrl+C before connection initialization is
complete.
-- Using DRCP on Windows with SQLNET.AUTHENTICATION_SERVICES
set to NTS.
-- Connection timeout due to SQLNET.INBOUND_CONNECT_TIMEOUT
parameter when all shared servers are busy in
shared server configuration.
*Action: Check Oracle Net administration in the following ways:
-- When using TNSNAMES.ORA or an Oracle Names server, make sure
that the client connection to the Oracle server uses
the correct service name or SID.
-- Check LISTENER.ORA on the connection end point's host machine
to assure that this service name or SID refers
to the correct server.
-- Confirm in TNSNAMES.ORA or the equivalent service definition
that the connect string does not contain (HS=).
-- Set SQLNET.AUTHENTICATION_SERVICES to NONE when using DRCP
on Windows.
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