Linux User-Group Console

This post shows you how to add the menu option and GUI to set users and groups. It’s quite a bit easier than mastering all the command-line syntax. It makes setting up the required user and group accounts for an Oracle Enterprise or MySQL database solution much easier.

You add the utility by calling the yum (Yellowdog Updater, Modified) utility like this:

yum installed -y system-config_users

You should see the following:

Loaded plugins: langpacks
Usage:  (more...)

Friday Spotlight: Video – Deploying and Upgrading OpenStack with Docker

OpenStack is notoriously complex to deploy and update. Traditional method of using RPMs is extremely unreliable due to inter-dependencies resulting into delays in deployment and failures in update. Any change in any of the RPMs may can adversely impact other RPMs and the deployment risks failures and delays.

Leveraging OpenStack upstream Kolla project, Oracle has transformed the deployment. OpenStack services are deployed as micro-services in docker containers which are fully independent from each other. Using (more...)

Oracle SGA memory allocation on startup

Recently I have been presenting on what running on a large intel based NUMA system looks like (OTN EMEA tour in Düsseldorf and Milan, and I will be presenting about this at the Dutch AMIS 25th anniversary event in june). The investigation of this presentation is done on a SGI UV 300 machine with 24 terabyte of memory, 32 sockets (=NUMA nodes), 480 core’s and 960 threads.

Recently I have been given access to a (more...)

Fix VMware Networking

Occasionally, my students loose their network connection when copying their virtual machines. This article shows you how to rebuild your Internet connection.

The first step requires you to identify the port number on your host operating system, which is typically Windows OS or Mac OS X. You can find that by running the following search from a Mac OS X Terminal session or Windows OS Command session.

If you’re on the Mac OS X, you (more...)

Automatic install of SOA Suite and Service Bus 12cR2.

Lately I worked on a set of scripts to automatically install Weblogic Infrastructure, SOA/BPM Suite, Service Bus, etc. Since I implemented a reworked set yesterday at another customer it might be nice to describe them here.

The scripts help in installing the software and creating the Repository. I started to create a script for creating the domain, but haven't it working yet. A good starting poing would be this blog of Edwin Biemond for the (more...)

FRIDAY SPOTLIGHT: Oracle Linux 6.8 is now available

On Monday evening, we released Oracle Linux 6.8 to the Unbreakable Linux Network.  This release is the first ISO to incorporate Unbreakable Enterprise Kernel Release 4 (Quarterly Update 1) and includes several improvements and features.  You can download this update from or from the Oracle Software Delivery Cloud.  For more information regarding the release or for details on how to update your system, please review the release notes located here.

 This (more...)

Training Thursdays: What You Need To Get Working on Oracle Linux 7

If you want to tap into the power of Oracle Linux 7 and already have experience as a Linux system administrator, then you need to learn to:

  • Perform common system administration tasks in Oracle Linux 7.
  • Configure the boot process, system logging, storage, and security.
  • Use advanced package management features.
  • Configure network bonding, VLANs, and VPNs.
  • Implement Docker containers.
  • Allocate system resources to specific Linux processes.

You can learn this and more by taking the (more...)

Under the Covers of OBIEE 12c Configuration with sysdig

OBIEE 12c has changed quite a lot in how it manages configuration. In OBIEE 11g configuration was based around system MBeans and the biee-domain.xml as the master copy of settings – and if you updated a configuration directly that was centrally managed, it would get reverted back. Now in OBIEE 12c configuration can be managed directly in text files again – but also through EM still (not to mention WLST). Confused? Yep, I (more...)

Experimenting with the ZFSSA’s snapshot capability using the simulator

Recently I have been asked how the Copy-on-Write cloning works on the ZFS Storage Appliance. More specifically, the question was about the “master” copy: did it have to be static or could it be rolled forward? What better than a test to work out how it works. Unfortunately I don’t have an actual system available to me at home so I had to revert to the simulator, hoping that it represents the real appliance accurately.


Trouble with multiple SCAN listeners in 12c Release 1

Prompted by comments made by readers about my posts describing how to add a second SCAN in 12c Release 1 and problems regarding the listener_networks parameter I thought it was time to revisit the situation. I’m still running Oracle Linux 7.1/UEK3 (although that should not matter) but upgraded to This is the release that is reportedly showing the odd behaviour. I don’t recall my exact version when I wrote (more...)

Getting a C++11 compiler for Node 4, 5 and 6 on Oracle Linux 6

| May 1, 2016
A newer compiler is needed on Oracle Linux 6 when you want to use add-ons like node-oracledb with Node 4 or later. This is because add-ons for those versions need to be built with a C++11 compatibile compiler. The default compiler on OL 6 doesn't have this support. OL 7 does have such a compiler, so these... [Read More]

New Installation Cookbook: Oracle Linux 6.7 with Oracle RAC

cookbookI’ve updated my install cookbooks page to include a new cookbook for installation of Oracle Real Application Clusters on Oracle Linux 6.7.

This is also the first one I’ve published since I left the employment of Violin Memory to work for Kaminario, so this install uses a Kaminario K2 All Flash Array. However, it applies very well to any Oracle RAC installation which uses relatively capable storage.


Filed (more...)

New OTN Article – OBIEE Performance Analytics : Analysing the Impact of Suboptimal Design

I’m pleased to have recently had my first article published on the Oracle Technology Network (OTN). You can read it in its full splendour and glory (!) over there, but I thought I’d give a bit of background to it here and the tools demonstrated within.

OBIEE Performance Analytics Dashboards

One of the things that we frequently help our clients with is reviewing and optimising the performance of their OBIEE systems. As part (more...)

SystemTap Guru Mode and Oracle SQL Parsing

Introduction and motivations

SystemTap and dynamic tracing tools in general give administrators great control on their systems with the relatively little additional effort to learn the new tools. In this post you will see of how SystemTap that can be used to modify data on the fly at runtime. The outcome is a form of "live patching". Examples are provided on how to apply these ideas to Oracle SQL parsing functionality. This type of "guru mode" use (more...)

Poll a Microsoft Exchange mailbox from OSB using DavMail

The Oracle Service Bus has built in features to poll an IMAP of POP3 mail account. There are loads of excellent blog posts that exactly describe how to do it. However, when the mail server happens to be a Microsoft Exchange server, things become shady. Exchange’s IMAP implementation tends to be not really that compatible, and the server log will fill up with stacktraces such as:

javax.mail.MessagingException: Connect failed;
  nested exception is:
        java. (more...)

Automatic install SOA/BPM QuickStart under Linux

Earlier I wrote about the automatic or silent install of JDeveloper. As a preperation for an automatic install of the complete SOASuite I translated this to Linux.

To do so in Linux you'll need to adapt the sudoers file.

Log in als root via het commando
[oracle@darlin-vce-db ~]$ su -
Last login: Fri Feb 26 06:44:05 EST 2016 on pts/0

Then edit the sudo-ers file:
[root@darlin-vce-db ~]# vi /etc/sudoers
Uncomment the lines for the (more...)

Oracle Linux 7 disks and udev

I was setting up disk devices for ASM in Oracle Linux 7. I knew things have changed between Oracle Linux 6 and Oracle Linux 7, but only just a little bit.

First of all, let’s take a look at the current disk usage. To see what disk devices are visible and how they are used, use lsblk:

# lsblk
fd0           2:0    1    4K  0 disk
sda           8:0    0    (more...)

The Oracle wait interface granularity of measurement

The intention of this blogpost is to show the Oracle wait time granularity and the Oracle database time measurement granularity. One of the reasons for doing this, is the Oracle database switched from using the function gettimeofday() up to version 11.2 to clock_gettime() to measure time.

This switch is understandable, as gettimeofday() is a best guess of the kernel of the wall clock time, while clock_gettime(CLOCK_MONOTONIC,…) is an monotonic increasing timer, which means it (more...)

PL/SQL context switch, part 2

This is the second blogpost on using PL/SQL inside SQL. If you landed on this page and have not read the first part, click this link and read that first. I gotten some reactions on the first article, of which one was: how does this look like with ‘pragma udf’ in the function?

Pragma udf is a way to speed up using PL/SQL functions in (user defined function), starting from version 12. If you want (more...)

Linux Perf Probes for Oracle Tracing

Topic: this post is about Linux perf and uprobes for tracing and profiling Oracle workloads for advanced troubleshooting.


The recent progress and maturity of some of the Linux dynamic tracing tools has raised interest in applying these techniques to Oracle troubleshooting and performance investigations. See Brendan Gregg's web pages for summary and future developments on dynamic traces for Linux. Some recent work on applying these tools and techniques to Oracle can be found (more...)