Cause: The database SID supplied in the
database login string was not recognized by the remote host.
Action: Ask your system administrator to
add the appropriate SID entry to oratab on the remote
host.

Relared Errors:
ORA-06721: TLI
Driver: spurious client req
ORA-06722: TLI
Driver: connection setup failure
ORA-06730: TLI
Driver: unable to open clone device
ORA-06731: TLI
Driver: cannot alloc t_call
ORA-06732: TLI
Driver: cannot alloc t_discon
ORA-06733: TLI
Driver: failed to receive disconnect
ORA-06734: TLI
Driver: cannot connect
ORA-06735: TLI
Driver: client failed to close error conn
ORA-06736: TLI
Driver: server not running
ORA-06737: TLI
Driver: connection failed