Oracle 11gR2 RAC cannot connect to the database through scanIP on the client

After installing Oracle 11g rac. the scanip is configured in ora, but it cannot be accessed. The error is that the target host does not exist. It has been tossing for a long time and I have not figured it out. Later I found that local_listener is included in the system initialization parameter, here, you can modify the host value, register the scanip, and use the vip in the listener!

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On the racnode1 Server:

[Root @ racdb1 ~] # Su-oracle
[Oracle @ racdb1 ~] $ Sqlplus/nolog
 

SQL * Plus: Release 11.2.0.1.0 Production on Wed Apr 21 13:44:12 2010
Copyright (c) 1982,200 9, Oracle. All rights reserved.
SQL> conn/as sysdba
Connected.
SQL> show parameter local_listener;
NAME TYPE VALUE
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Local_listener string (DESCRIPTION = (ADDRESS_LIST = (AD
DRESS = (PROTOCOL = TCP) (HOST = racw.vip) (PORT = 1521 ))))

SQL> alter system set local_listener = '(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = racscan) (PORT = 1521 )))) 'scope = both sid = 'racdb1 ';
System altered.
SQL>
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The same is true for node 2.