Oracle 11g out-of-place vs. in-place database upgrades

Starting with Oracle 11gR2, Oracle changed their patching strategy.

Previously, a patch set was supposed to be downloaded and installed into an existing ORACLE_HOME.
After 11.2, a "patch set" is really a full release, bundled in a number of zip files.

The default patching method is the "out-out-place", which means that every time customers need to upgrade to a new patch set (say, 11.2.0.4), a new ORACLE_HOME should be created, and the new binaries should be installed here.

So you will potentially end up with a number of ORACLE_HOME on your server, and you can choose to run your database out of either of these, upgrading whenever you please.

See Mike Dietrich's post about the same topic for more details.

How to fix error thrown by OPatch: java.lang.NullPointerException

Problem:

Opatch throws the following error when you are querying the inventory:

[oracle@lx01 ~]$ opatch lsinventory
Oracle Interim Patch Installer version 11.2.0.3.11
Copyright (c) 2015, Oracle Corporation.  All rights reserved.


Oracle Home       : /u01/oracle/product/11.2.0/dbhome_1
Central Inventory : /u01/oraInventory
   from           : /u01/oracle/product/11.2.0/dbhome_1/oraInst.loc
OPatch version    : 11.2.0.3.11
OUI version       : 11.2.0.1.0
Log file location : /u01/oracle/product/11.2.0/dbhome_1/cfgtoollogs/opatch/opatch2015-09-02_08-52-28AM_1.log

Lsinventory Output file location : /u01/oracle/product/11.2.0/dbhome_1/cfgtoollogs/opatch/lsinv/lsinventory2015-09-02_08-52-28AM.txt

--------------------------------------------------------------------------------
java.lang.NullPointerException
 at oracle.sysman.oii.oiin.OiinNetOps.addNICInfo(OiinNetOps.java:144)
 at oracle.sysman.oii.oiin.OiinNetOps.computeNICList(OiinNetOps.java:109)
 at oracle.sysman.oii.oiin.OiinNetOps.(OiinNetOps.java:76)
 at oracle.sysman.oii.oiin.OiinNetOps.getNetOps(OiinNetOps.java:90)
 at oracle.sysman.oii.oiix.OiixNetOps.getFullHostName(OiixNetOps.java:49)
 at oracle.opatch.LsInventoryPrinter.printLocalMachineInfo(LsInventoryPrinter.java:2336)
 at oracle.opatch.LsInventorySession.loadAndPrintInventory(LsInventorySession.java:480)
 at oracle.opatch.LsInventorySession.process(LsInventorySession.java:317)
 at oracle.opatch.OPatchSession.main(OPatchSession.java:2120)
 at oracle.opatch.OPatch.main(OPatch.java:626)
Local Machine Information::
Hostname: lx01.oric.no
ARU platform id: 226
ARU platform description:: Linux x86-64

Installed Top-level Products (1): 

Oracle Database 11g                                                  11.2.0.1.0
There are 1 products installed in this Oracle Home.


There are no Interim patches installed in this Oracle Home.


--------------------------------------------------------------------------------

OPatch succeeded.

Cause:
In my case, the file /etc/hosts was incorrectly configured.

Solution:
Configure the file /etc/hosts correctly.

[root@lx01 ~]# ifconfig 
enp0s3: flags=4163  mtu 1500
        inet 192.168.0.55  netmask 255.255.255.0  broadcast 192.168.0.255

Check the /etc/hosts:

[root@lx01 ~]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.55 lx01.oric.no lx01
[oracle@lx01 ~]$ vi /etc/hosts

Update the incorrect ip address from 192.168.1.55 to 192.168.0.55, and save the file.

Opatch will now display expected output:

[oracle@lx01 ~]$ opatch lsinventory
Oracle Interim Patch Installer version 11.2.0.3.11
Copyright (c) 2015, Oracle Corporation.  All rights reserved.


Oracle Home       : /u01/oracle/product/11.2.0/dbhome_1
Central Inventory : /u01/oraInventory
   from           : /u01/oracle/product/11.2.0/dbhome_1/oraInst.loc
OPatch version    : 11.2.0.3.11
OUI version       : 11.2.0.1.0
Log file location : /u01/oracle/product/11.2.0/dbhome_1/cfgtoollogs/opatch/opatch2015-09-02_09-07-43AM_1.log

Lsinventory Output file location : /u01/oracle/product/11.2.0/dbhome_1/cfgtoollogs/opatch/lsinv/lsinventory2015-09-02_09-07-43AM.txt

--------------------------------------------------------------------------------
Local Machine Information::
Hostname: lx01.oric.no
ARU platform id: 226
ARU platform description:: Linux x86-64

Installed Top-level Products (1): 

Oracle Database 11g                                                  11.2.0.1.0
There are 1 products installed in this Oracle Home.


There are no Interim patches installed in this Oracle Home.


--------------------------------------------------------------------------------

OPatch succeeded.

How to solve: error while loading shared libraries: libaio.so.1: cannot open shared object file: No such file or directory

After a fresh install of an Oracle 32-bit client on a 64-bit Linux server, we received the following errors when we tried to use any of the binaries under the $ORACLE_CLIENT_HOME/bin directory:

 error while loading shared libraries: libaio.so.1: cannot open shared object file: No such file or directory

It turned out that only the 64-bit version of libaio was installed:

yum list libaio
Loaded plugins: product-id, rhnplugin, security
This system is receiving updates from RHN Classic or RHN Satellite.
Installed Packages
libaio.x86_64  0.3.107-10.el6  @anaconda-RedHatEnterpriseLinux-201301301459.x86_64/6.4
Available Packages
libaio.i686  0.3.107-10.el6  prod-rhel-x86_64-server-6

Solution is to simply install the missing package (output abbreviated):

su -
yum install libaio.i686

downloading Packages:
libaio-0.3.107-10.el6.i686.rpm                                                                                                                                                                    |  21 kB     00:00
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing : libaio-0.3.107-10.el6.i686                                                                                                                                                                            1/1
  Verifying  : libaio-0.3.107-10.el6.i686                                                                                                                                                                            1/1

Installed:
  libaio.i686 0:0.3.107-10.el6

Complete!

How to create a symlink in unix

Syntax:
ln -s /path/physical_file symlink

For example

cd $ORACLE_HOME/lib
ln -s /u01/oracle/product/oracle_client32/lib/libclntsh.so.11.1 libclntsh.so
ls -altr libclntsh.so
libclntsh.so -> /u01/oracle/product/oracle_client32/lib/libclntsh.so.11.1

What does the DEFAULT DEGREE on tables actually mean?

The DOP (degree of parallelism) settings on a table has to do with the number of threads per instance for scanning the table (an integer), or DEFAULT.

When a tables DEGREE setting is set to DEFAULT, it means that the DOP) is calculated via the following formula:

For a single instance:

DOP = PARALLEL_THREADS_PER_CPU x CPU_COUNT

For an Oracle RAC configuration:

DOP = PARALLEL_THREADS_PER_CPU x CPU_COUNT x INSTANCE_COUNT

The DOP for a table can be viewed in either of the *_TABLES views.

SELECT DEGREE
FROM   DBA_TABLES
WHERE  TABLE_NAME = 'EMP'
AND    OWNER = 'SCOTT';


DEGREE
------------------
         1

How to use cpio on AIX

I recently received a patch from Oracle support, and when unpacking with unzip, the resulting file was in the cpio format. Unpacking this file, in turn, is done like this:

mkdir install
cd install
cpio -idcmv < 9205_aix5l64_release.cpio

How to create and how to extract a .tar file

Create a tar file of all the files in the current directory:

tar cvf myfile.tar *

or put it in a different directory:

 tar cvf $HOME/myfile.tar *

To extract myfile.tar to the current directory

tar xvf myfile.tar 

To a specific directory:

tar xvf myfile.tar -C mydir