Category Archives: linux

hp-ux, linux, RAC, unix

Unable to mount OCFS2 drives

Leave a comment

Oracle provides the file system OCFS2 to support Oracle RAC file storage. This file system provides for a locking mechanism which allows files to be accessed by multiple Oracle instances while avoiding corruption. The OSFS2 file system binaries must be started before any OCFS2 formatted mount points can be accessed. This article shows the error generated when the OCFS2 stack has not been started and how to resolve the problem.

General OS error:

[root@mylinux init.d]# mount /dev/mapper/MPATH10 /u02
mount.ocfs2: Unable to access cluster service while trying initialize cluster

Resolution:

1. Logon to your server as root.
2. Change directory to /etc/init.d

[root@mylinux /]# cd /etc/init.d
[root@mylinux init.d]# pwd
/etc/init.d
[root@mylinux init.d]#

3. Execute the OS layer command ./ocfs2 load.

[root@mylinux init.d]# ./o2cb load
Loading filesystem “configfs”: OK
Mounting configfs filesystem at /sys/kernel/config: OK
Loading filesystem “ocfs2_dlmfs”: OK
Mounting ocfs2_dlmfs filesystem at /dlm: OK
[root@mylinux init.d]#

4. Execute the OS layer command ./ocfs2 online

[root@mylinux init.d]# ./o2cb online
Starting O2CB cluster ocfs2: OK
[root@mylinux init.d]#

5. Attempt to mount your ocfs2 storage device.

[root@mylinux init.d]# mount /dev/mapper/MPATH10 /u02
[root@mylinux init.d]#

6. This completes restarting OCFS2 binaries.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

linux, Oracle

Disabling SELinux before Oracle installation

Leave a comment

SELinux (Security-Enhanced Linux) provides for additional OS layer security with a default installation. However, this added security can cause issues for installation of multiple software packages of which Oracle is one. This article shows how to disable SELinux before Oracle installation.

1. Logon to your server as root.
2. Open the file /etc/selinux/config with vi.

[root@mylinux /]# vi /etc/selinux/config
# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
# enforcing – SELinux security policy is enforced.
# permissive – SELinux prints warnings instead of enforcing.
# disabled – SELinux is fully disabled.
SELINUX=permissive
# SELINUXTYPE= type of policy in use. Possible values are:
# targeted – Only targeted network daemons are protected.
# strict – Full SELinux protection.
SELINUXTYPE=targeted
~

3. Disable SELinux by changing the option SELINUX to disabled.

SELINUX=disabled

4. Reboot your Linux server for the changes to take affect.

5. This completes disabling of SELinux before Oracle installation.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

linux, Oracle

Determining SELinux mode before Oracle installation

Leave a comment

SELinux (Security-Enhanced Linux) provides for additional OS layer security with a default installation. However, this added security can cause issues for installation of multiple software packages of which Oracle is one. This article shows how to determine the mode of SELinux before installing Oracle.

1. Logon to your server as root.
2. Execute the command getenforce or sesstatus to determine the current OS mode of SELinux.

[root@mylinux /]# /usr/sbin/getenforce
Permissive
[root@mylinux /]# /usr/sbin/sestatus
SELinux status: enabled
SELinuxfs mount: /selinux
Current mode: permissive
Mode from config file: permissive
Policy version: 21
Policy from config file: targeted
[root@mylinux /]#

3. This completes determination of SELinux mode before Oracle installation.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

11g, installer, linux, OPatch, unix

Oracle error OUI-10058

Leave a comment

The OUI (Oracle Universal Installer) relies on an Oracle inventory to recognize the Oracle software which already exists on the system. Multiple files are read during the OUI startup, the first of which is /etc/oraInst.loc. The oraInst.loc file points to the location of the Oracle inventor directory, which could be anywhere. In order to get an inventory of the current system, OUI must have access to this file. The error OUI-10058 is an indication that OUI does not have access to this file. This article covers the typical error and resolution to this problem

Typical error:

OUI-10058 The OUI Inventory on this system does not exist or is not writable.
1. The /opt/oracle/oraInventory/orainstall…..
or
2. You are not a member of the specified installer group.


Solution: If you executed all previous root.sh script as instructed, the most like cause is permission.

1. Logon to the system as root.
2. Change directory to /etc
3. Check the file permissions with the command ll

[root@mylinux /]# ll *ora*

4. If the file permission is not set to 644, change the permissions with the command chmod

[root@mylinux /]# chmod 644 /etc/oraInst.loc.

5. This completes the resolution of OUI-10058, due to file permissions of /etc/oraInst.loc.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

11g, hp-ux, linux, Oracle 10g, oracle 9i, unix

Oracle Error ORA-25153

Leave a comment

Oracle Error ORA-25153 is a regular occurrence during the modification of location or recreation of an Oracle database. It indicates that the administrator neglected to add datafiles to a temporary tablespace. This article provides a solution the error ORA-25153, if it occurs.

Typical Error message:

Errors in file /u01/app/oracle/product/10.2.0/db_1/admin/orcl/bdump/orcl_j001_25535.trc:
ORA-25153: Temporary Tablespace is Empty
Sun Sep 19 01:31:00 2010
Thread 1 advanced to log sequence 9 (LGWR switch)
Current log# 3 seq# 9 mem# 0: /u05/oradata/orcl/group_3.dbf

Solution:

1. Logon to your Oracle database server as the Oracle software owner.

2. Logon to SQLPLUS with SYSDBA privileges.

mylinux:> sqlplus ‘/ as sysdba’

SQL*Plus: Release 10.2.0.4.0 – Production on Sun Sep 19 08:08:39 2010

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 – 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL>

3. Add a temp file to your default temporary tablespaces with the following syntax: alter tablespace add tempfile < 'directory and file name'> size ;

example:


SQL> alter tablespace temp add tempfile ‘/u05/oradata/orcl/temp01.dbf’ size 2048m;

Tablespace altered.

SQL>

4. This completes the resolving of Oracle error ORA-25153.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

linux, Oracle 10g, RAC, unix

Enabling Oracle RDBMS RAC features

Leave a comment

The determination of Oracle binary support for Real Application Clustering is made during installation on all supported platforms. Thus, an installation made for a single instance database will not support creation of RAC by default. However, you can modify the binaries to support these features after installation. This article details the steps to modify your Oracle binaries to support Oracle RAC.

1. Logon to your Oracle database server as the Oracle software owner.

2. Change directory to your ORACLE_HOME/rdbms/lib.

cd $ORACLE_HOME/rdbms/lib

3. Use make to recreate your Oracle binaries with the option rac_on

make -f ins_rdbms.mk rac_on

4. Change directory to your ORACLE_HOME/bin.

5. Execute the utility relink with option all, to recreate all binary files.

relink all

6. This completes altering your Oracle RDBMS binaries to support Oracle RAC features.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

linux, Oracle, Oracle 10g, RAC, unix

Manually initializing Oracle OCFS2 stack

Leave a comment

Oracle provides the file system OCFS2 to support Oracle RAC file storage. This file system provides for a locking mechanism which allows files to be accessed by multiple Oracle instances while avoiding corruption. The OSFS2 file system binaries must be started before any OCFS2 formatted mount points can be accessed. This article shows the error generated when the OCFS2 stack has not been started and how to resolve the problem.

General OS error:


[root@mylinux /]# mount /dev/mapper/MPATH10 /u02
mount.ocfs2: Unable to access cluster service while trying initialize cluster

Resolution:

1. Logon to your server as root.
2. Execute the OS layer command /etc/init.d/o2cb enable

[root@mylinux /]# /etc/init.d/o2cb enable
Loading filesystem “configfs”: OK
Mounting configfs filesystem at /sys/kernel/config: OK
Loading filesystem “ocfs2_dlmfs”: OK
Mounting ocfs2_dlmfs filesystem at /dlm: OK
[root@mylinux /]#

3. Execute the OS layer command /etc/init.d/o2cb start

[root@mylinux /]# /etc/init.d/o2cb start
Starting O2CB cluster ocfs2: OK
[root@mylinux /]#

4. Attempt to mount your ocfs2 storage device.

[root@mylinux /]# mount /dev/mapper/MPATH10 /u02
[root@mylinux /]#

5. This completes restarting OCFS2 binaries.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

11g, hp-ux, itanium, linux, network, Oracle, Oracle 10g, oracle 9i

Oracle NETCA – Network Configuration assistant.

Leave a comment

Oracle provides several Configuration Assistant tools to facility administrative duties required by an Oracle DBA or Developer. The Oracle’s NETCA (Network Configuration Assistant) is the GUI tool used to configure the network components of your Oracle RDBMS. In this article we will review the startup of the Network Configuration Assistant within a RHEL environment.

1. Logon to your Oracle Database server as the Oracle software owner.
2. Change directories to your $ORACLE_HOME/bin.

mylinux:> cd $ORACLE_HOME/bin
mylinux:>

3. Export your display to your local machine if you are not logon to the server itself.

mylinux:> export DISPLAY=192.168.0.110:0.0
mylinux:>

4. You will require a terminal emulation program executing on your local machine to produce the display from your database server. Any terminal display software will do, however I would suggest VNC which can be downloaded for free at the URL: www.realvnc.com

5. Execute the dbca shell script to startup the database configuration assistant.


mylinux:> ./netca

6. The Network Configuration Assistant is self explanatory from here on. It allows the ability to configure, add, delete and modify you various Oracle networking components.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com

11g, ASM, hp-ux, itanium, linux, Oracle, Oracle 10g, oracle 9i, unix

Oracle DBCA – Database Configuration assistant.

Leave a comment

Oracle provides several Configuration Assistant tools to facility administrative duties required by an Oracle DBA or Developer. The Oracle’s DBCA (Database Configuration Assistant) is the GUI tool used to create starter databases within the Oracle RDBMS. The DBCA utility was introduced in Oracle 8i and provides the user a GUI to eliminate the need for manual configuration of database creation scripts. In this article we will review the startup of the Database Configuration Assistant within a RHEL environment.

1. Logon to your Oracle Database server as the Oracle software owner.
2. Change directories to your $ORACLE_HOME/bin.

mylinux:> cd $ORACLE_HOME/bin
mylinux:>

3. Export your display to your local machine if you are not logon to the server itself.

mylinux:> export DISPLAY=192.168.0.110:0.0
mylinux:>

4. You will require a terminal emulation program executing on your local machine to produce the display from your database server. Any terminal display software will do, however I would suggest VNC which can be downloaded for free at the URL: www.realvnc.com

5. Execute the dbca shell script to startup the database configuration assistant.

mylinux:> ./dbca

6. The Welcome screen will display and the wizard from here on is pretty self explanatory. The DBCA utility provides you the ability to Create Databases, Configure Database Options, Delete Databases, Manage Database Templates, and Configure ASM instances for storage.

Larry J. Catt, OCP 9i, 10g
oracle@allcompute.com
www.allcompute.com