Problems and Solutions after Oracle 11g upgrade

Lab environment, Oracle 11gR2 standalone test data software and database upgrade, operating system Linux6.3
Oracle version 11.2.0.1 upgrade package 11.2.0.3
After the database software and database are upgraded successfully, the following error is always prompted when you test the export full database experiment of expdp:

[Oracle @ linuxtest ~] $ Expdp oracle/oracle @ orcl directory = DATA_PUMP_DIR dumpfile = daochu. dmp logfile = daochu. log full = yes

Export: Release 11.2.0.3.0-Production on Mon Oct 28 09:47:18 2013

Copyright (c) 1982,201 1, Oracle and/or its affiliates. All rights reserved.

UDE-12154: operation generated ORACLE error 12154
ORA-12154: TNS: cocould not resolve the connect identifier specified

1. Try the following solution as prompted:
Sqlplus/as sysdba CONNECT to the database, grant create user, drop user, alter user, create any view, drop any view, EXP_FULL_DATABASE, IMP_FULL_DATABASE, DBA, CONNECT, RESOURCE, create session to oracle (username) Here I select the new oracle user.
Then I checked the lisenter. ora and tnsnames. ora files and found they were all normal. But I used the netca command to re-create the listener and then tested the expdp to find the same problem.

2. Final Solution:
Su-oracle users can view the listening file and find the following problems:
[Oracle @ linuxtest admin] $ cat tnsnames. ora
Cat: tnsnames. ora: Permission denied

The prompt is that the permission is insufficient. It was previously viewed under the root user, so I did not notice this problem. So I guess the problem lies in the permission of the oracle home Directory.

At the beginning of the experiment, when I upgraded the database software, oracle prompts that the oracle_home directory cannot be the same as the previous one, that is, the new directory must be created. Later, I chose to create the 11.2.3 subdirectory under the original oracle_home directory, at the same time, the subdirectory of 11.2.0 still exists. Follow the prompt chown-R oracle: oinstall/oracle/* to re-grant the permission to the oracle_home directory, and view the listening file again under the oracle user to find that it can be read.

Try to export the full database of expdp and find that the export operation is normal.

Recommended reading:

How to install Oracle 11g on Linux

Detailed description of the installation process of Oracle 11g Database in Linux

How to install Oracle 11g R2 single-instance database on CentOS 5.6

To install Oracle Clusterware on an Oracle vmvm

Install Oracle 11 GB single-instance database on Linux under vmvm