I’m talking about the ‘third’ field in the database entries. Field number three. Which indicates there could be a fourth, fifth etc… right?
A customer where I came (who went from AIX to Linux), who had interpreted this comment and therefore expanded the oratab with an extra column, to datapump the database (y/n).
When I shut down the databases, there was some unexpected behaviour when I invoked dbshut… Strange, but the extra (last) field ‘for datapump’ was read, not the third!
SOLVED: this issue is solved in Linux 6.4 (kernel: 2.6.39-400.17.1.el6uek and 2.6.32-358.el6).
A single entry in /etc/fstab like [tmpfs /dev/shm tmpfs size=3g 0 0] now works as it should!
There is a bug in Red Hat Linux 6 and Oracle Enterprise Linux 6 (UEK and RHEL-kernel) and probably all other Red Hat 6 related Linux Distro’s.
When you need more memory for SGA/PGA when using MEMORY_MAX_TARGET, you need to resize /dev/shm. By default this is 50% of total memory and Oracle tells you to add the following to /etc/fstab, ‘mounting’ the /dev/shm twice (?):
tmpfs /dev/shm tmpfs size=3g 0 0
(IMPORTANT NOTE: make sure the first field (fs_spec) ‘shmfs’ has the same name as the already existing ‘defaults’ name). So if you have a line [tmpfs /dev/shm tmpfs defaults 0 0], make sure the ‘overruled’ line also starts with ‘tmpfs’: [tmpfs /dev/shm tmpfs size=3g 0 0]. If not, a `mount -a` will un-mount (!!!) the ‘shmfs’ and remount ‘tmpfs’, this results in immediate clearing the ‘/dev/shm’ memory and all your SGA is instantly gone! Running this when databases are running, your databases with AMM will crash! This ‘issue’ is still there last time checked in Linux 7.3. In Oracle documentation about /dev/shm, the first field is ‘shmfs’ with can result in crashing databases when a `mount -a` done!
A couple of days ago I did a new install of the Oracle Database Software (on a Virtual Machine) and it kept failing. I got some oracle.cluster.verification.VerificationException error, but I could not get more information from the logs. Usually it’s a bit more detailed after the colon, but this time it just said: [hostname]: [hostname]. Continue reading
You can update your Oracle VM Servers (3.x) with the Oracle Public Yum Server. In the Oracle VM Manager console go to the ‘Tools and Resources’ tab and click ‘Server Update Management (YUM)’.
For the ‘YUM Base URL:’, use:
When enabling the GPG key, use:
(Oracle VM 3.x is based on OEL5) Continue reading
In Oracle Linux 6, it looks like the ‘oracle-validated’ package is missing, but Oracle actually renamed it to ‘oracle-rdbms-server-11gR2-preinstall.x86_64‘.
To quickly use the public yum repository of Oracle and install ‘oracle-rdbms-server-11gR2-preinstall.x86_64’:
yum clean all
yum install oracle-rdbms-server-11gR2-preinstall.x86_64
You will get the ‘latest’ build enabled.
If you don’t want this, vi /etc/yum.repos.d/public-yum-ol6.repo .
Today I ran into an add-on for FireFox which can create a wget command from a download file dialog box. First thing that came in mind was; Will this work for Metalink / My Oracle Support? Yes is does!
The add-on is called ‘cliget’ and can be downloaded here: cliget add-on for FireFox. Continue reading
[Commands used were against VirtualBox version 4…]
Sometimes you don’t want to use a lot of disk space on your VirtualBox for install software or any ‘temporary’ need of space.
Adding shared folders from your host to your VirtualBox guest is a good option to use. If you have a Windows guest and a GUI based Host, it it’s very easy; click, click, done.
But if you are using a command line based guest and/or host, it a bit more complex. Use this post as a guideline, Linux knowledge is assumed… Continue reading
The Easy Connect Naming Method allows you to connect to a database service without having to configure Net Service Names.
The most found example on internet is the one with typing the password at the command prompt when starting sqlplus:
$> sqlplus system/manager@db_machine:1521/db_servicename
However, this means that the password will be stored in you history of commands (linux). This is not really secure… but sqlplus does not accept it when no password is supplied when using easy connect.
If you want to login with easy connect without typing the password on the command line, you have two options: Continue reading
I was preparing some fresh installed OEL5.5 machines for database software installation, but after running ‘yum install oracle-validated‘, the OUI did not pass the prerequisites on two packages. It seems it did not install unixODBC-devel x86_64 and libaio-devel x86_64.
Their Linux may be unbreakable, but their ‘oracle-validated’ package on the public yum server seemed to be broken. Continue reading
Many people will use the WebLogic’s NodeManager to use the start script for starting Managed Servers:
The NodeManager will start the Managed Server using the script and monitor the Managed Server when it fails.
One of the mistakes people can make is creating their own start script and start the Managed Server using ‘nohup &’ within this script: Metalink [ID 984122.1] and [ID 861098.1]. The script will finish and the server keeps running, but the NodeManager thinks the Managed Server has failed… Continue reading