Exadata and WebLogic CVE-2019-2725

I can still remember the surprise when Frits Hoogland pointed out that Oracle had replaced the old OC4J instance on Exadata storage servers with a WebLogic service. I wasn’t quite sure what to make of this, but it’s become apparent as things move cloudward that it would enable an entire set of REST operations for Exadata on both storage and compute tiers. This becomes interesting due to the recent 0-day vulnerability for WebLogic, CVE-2019-2725. According (more...)

Bloom Filter Efficiency And Cardinality Estimates

I've recently came across an interesting observation I've not seen documented yet, so I'm publishing a simple example here to demonstrate the issue.

In principle it looks like that the efficiency of Bloom Filter operations are dependent on the cardinality estimates. This means that in particular cardinality under-estimates of the optimizer can make a dramatic difference how efficient a corresponding Bloom Filter operation based on such a cardinality estimate will work at runtime. Since Bloom (more...)

Newly released: Oracle Exadata X8-2 – bigger disks for saving money, expanding capacity

imageEarlier this month, Oracle announced the availability of the latest Exadata machine, the X8-2. As well as the option to swap in big 14 TB disks in older versions of Exadata that were shipped with far smaller disks, allowing these older systems to substantially increase there capacity.

Our AMIS resident Exadata expert Michael Huisman analyzed the key aspects of Oracle’s announcement.

The changes in specifications compared to X7 are not huge. The most eye catching (more...)

12.2 Grid Patching lesson learned

What happend?

During the last month I updated manually the TFA Software.

I  do this update while the TFA release installed via the Patchset is an older Version. This happens while Oracle Support adds the TFA release which is available while they create the Patchset.

Last weekend I start Patching GI Software 12.2 to RU Oct 2018 on a 4 Node Exadata Cluster

As best practice I do the installation manually and not via (more...)

How to create an sosreport on Oracle Linux

When creating a SR for an issues on Oracle Linux, for example in an Exadata environment, you are quite often enough asked to run an sosreport.

What is sosreport?

“The “sosreport” is a tool to collect troubleshooting data on an Oracle Linux system. It generates a compressed tarball of debugging information that gives an overview of the most important logs and configuration of a Linux system, to be sent to Oracle Support.

Among other things, (more...)

Getting locale warnings when logging on to Linux

This blogpost is about the reason and solving getting the following message, or messages alike these when logging i to a linux box using ssh:

-bash: warning: setlocale: LC_CTYPE: cannot change locale (UTF-8): No such file or directory

However, this is a warning. Please mind such an issue might be come up in another way, which can be more disrupting; at least in the past I had issues running perl for the same issue:

[root@dmcel01 (more...)

Checking Flash Cache Mode in Exadata Cloud

While looking at an exachk report for an Exadata rack running in Oracle Cloud Infrastructure, I saw an interesting finding:

Since this is an Oracle cloud environment, we don’t have any access to view the storage servers – they are managed and maintained by Oracle.  For several reasons, I believed this to be a false alert, but wanted to see if I could determine what the flashcachemode setting is.

On some flavors of Exadata (more...)

Changing IP Addresses on InfiniBand Network with 12.2 GI on Exadata

I was tasked a while back with modifying the IP addresses assigned to the InfiniBand network on an X6-2 rack.  We were configuring a ZFS appliance to share between 2 Exadata clusters, and we wanted to keep them on separate network ranges.  In this case, we were moving the interfaces from 192.168.10.x/22 (the Exadata default network range) to 192.168.14.x/22. The process is documented very well by Oracle (more...)

Understanding grid disks in Exadata

Use of Exadata storage cells seems to be a very poorly understood concept. A lot of people have confusions about how exactly ASM makes uses of disks from storage cells. Many folks assume there is some sort of RAID configured in the storage layer whereas there is nothing like that. I will try to explain some of the concepts in this post.

Let’s take an example of an Exadata quarter rack that has 2 db (more...)

Oracle Database 19.2 for Exadata is available

Oracle 19.2 is available for Exadata on Premise

Yes, and the good news are ..

We actually setup a X7 with Oracle Linux 7 …. which is a prerequisite

I will prepare an article in the near future





exachk 18.4 does not run database

For all of you who use exachk and have updated to exachk Version 18.4. There is a known Bug on Oracle databases

While running exachk as root user the program try to connect to the database and this will no work.

You saw the following message:

„OS authentication is not enabled so please enter sysdba privileged user name for <User name>:- sys

Enter password for sys@<User name>:-

SELECT 1 FROM (more...)

Oracle’s Autonomous Database (Cloud)

So yesterday I attended the “Autonomous Database GTM Roadmap Sales Workshop” at Oracle’s London office.  This training is for Oracle partners such as Version 1, which is one of Oracle’s strategic partners.

A lot of what is in this blog post is subject to Oracle’s Safe Harbour statement.

Key Takeaways

1 . Maturity

The Autonomous Database is still very new!  It’s like back in 2008 when the first Exadata Machine (V1) (more...)

Flamegraph with function annotation

Recently, Franck Pachot tweeted the following:

This is a very clever way of using Brendan Gregg’s flame graphs for Oracle database process flame graphs and using my ora_functions project database.

However, the awk script uses a full match using f[$2]:
– f is an array with the function name annotations filled using {f[$1]=$2;next}.
– // means to only work on lines that have in it.
– The lines have the oracle function stuck to , (more...)

dbca doesn’t list diskgroups

This is an Exadata machine running GI version and DB version On one of the DB nodes while running dbca, it doesn’t list the diskgroups. it works fine on the other node.

I cheked the dbca trace and found that the kfod command was failing. I tried to run it manually and got the same error:

[oracle@exadb01 ~]$ /u01/app/ op=groups verbose=true
KFOD-00300:  (more...)

OBUG Tech Days Belgium 2019 – Antwerp – 7/8-FEB-2019

Agenda: https://www.techdaysbelgium.be/?page_id=507

Dates: February 7 and 8, 2019

Location: http://cinemacartoons.be in Antwerp, Belgium

More information soon.

For people from the netherlands: this is easy reachable by car or by train! This is a chance to attend a conference and meet up with a lot of well-known speakers in the Oracle database area without too extensive travelling.

New web based OEDA for Exadata

It started with an xls sheet (that was called dbm configurator) . Then OEDA (Oracle Exadata Deployment Assistant) was introduced that was a Java based GUI tool to enter all the information needed to configure an Exadata machine. Now with the latest patch released in Oct, OEDA has changed again; to become a web based tool. It is deployed on WebLogic and comes with some new features as well. SuperCluster deployments will continue to use the (more...)

opatch investigations

This blogpost is about opatch and how to obtain information about the current oracle home(s), and how to obtain information about the patches to be applied.

Patches that can be applied using opatch are provided by oracle as zip files which have the following naming convention:
p[patchnumber]_[baseversion]_[platform]-[architecture].zip. The patch normally contains an XML file called ‘PatchSearch.xml’ and a directory with the patch number. Inside the patch number directory there is a README.txt (more...)

opatch versions

This blogpost is about oracle’s patching tool for the database and grid infrastructure: opatch. I personally have a love/hate relationship with opatch. In essence, opatch automates a lot of things that would be very error prone if it were to be done by hand, which is a good thing. However, there are a lot of things surrounding opatch that I despise. An example of that is the version numbering of opatch itself.

Versions and more (more...)

Arbeitsgruppen Treffen „Engineered Systems“ in Nürnberg

Wie jedes Jahr trifft sich die Arbeitsgruppe „Engineered Systems“

am Vorabend der Konferenz.

Termin: Montag, den 19.11.2018, um 17:00 Uhr

Ort: Nürnberg, ConventionCenter Ost Messezentrum, 90471 Nürnberg

Der Raum befindet sich im Zwischengeschoss

Wir haben spannende Themen auf der Tagesordnung und das Oracle Exadata und ODA Product-Management ist ebenfalls vor Ort.

Es wird wie immer interessant mit vielen Neuigkeiten rund um die Engineered Systems

Das Networking kommt natürlich auch nicht zu kurz

Wir sehen (more...)

Oracle wait event ‘TCP Socket (KGAS)’

I was asked some time ago what the Oracle database event ‘TCP socket (KGAS)’ means. This blogpost is a deep dive into what this event times in Oracle database

This event is not normally seen, only when TCP connections are initiated from the database using packages like UTL_TCP, UTL_SMTP and the one used in this article, UTL_HTTP.

A very basic explanation is this event times the time that a database (more...)