ORA-12547: TNS Lost Contact when running DBCA on Oracle 11g installation on Ubuntu Linux 12.04 64 bit

I'm trying to create a database using DBCA on Oracle 11g installation on Ubuntu Linux 12.04 64 bit.

I followed the instructions here, but I get

ORA-12547: TNS Lost Contact when running DBCA.

Below are the details. Can someone assist with the solution?

1. Instead of using /opt/oracle as the "oracle" user home, I used /home/oracle

2. I did not install the libstdc++5 in 32 bit version

3. I did everything else the same as the posting

4. Installation resulted in "missing packages". I tried to do an apt-get install for these packages from ubuntu, but ubuntu says that they don't exist. Then I saw in the instructions:

   Once you will reach the "pre-reqs" screen, check "Ignore all" to continue the installation.

5. When running ./dbca from $ORACLE_HOME/bin, it fails with ORA-12547.

6. I checked $ORACLE_HOME/network/admin and listener.ora , sqlnet.ora , and tnsnames.ora all look OK.

7. However, I think that tnsnames.ora is not being read properly, because ./tnsping fails and the error message states that "EZ Connect" was used. But in my sqlnet.ora , I have

   names.directory_lookup = (TNSNAMES,EZCONNECT)

   It should use EZ Connect only after tnsnames is tried.

8. Also, I sometimes get ORA-12541: No listener. I tried running ./netca. Everything is OK until I perform a test on the listener, and it fails.

9. I can't run ./lsnrctl. Absolutely nothing happens for this, as well as lsnrctl start, stop, status.

10. I can't go through sqlplus. If I run ./sqlplus , it asks me for username/password directly.

11. If I do ./sqlplus / as sysdba, then this results in "ORA-12547: TNS lost contact".

12. All environment variables are set correctly in .bashrc.

13. I tried re-running root.sh , but the problem is not fixed.

14. /etc/oratab is OK

15. /etc/hosts is OK, but I can't always ping the "localhost" or "127.0.0.1", or "ubuntu" or "127.0.1.1"

    The same TNS or Listener errors display.

2 Answers

1. When I login in oracle (sqlplus system/pass as sysdba), I got this:

   ERROR: 　

   ORA-12547: TNS :lost contact when try to connect to Oracle.

2. First, I think the server is down, but I check it, it is OK. And so many body say 'chmod 6751 oracle', I did it, but I got another error:

   ERROR:

   ORA-01031: insufficient privileges

   Enter user-name:

3. finally, I switch the system user from root to oracle. And I login success.

Ensure the DB is up and running and you can connect locally AS SYSDBA to the database
using Oracle binaries owner (usually oracle:oinstall Unix / Linux user). If it does not
work, probably you encounter a different problem.
1. Check privileges of an Oracle file on Unix / Linux host where database is running: cd $ORACLE_HOME/bin ls -ltr oracle
2. Change permissions as below: chmod 6751 oracle ls -ltr oracle This code may help you lot.