Side effect of ExaWatcher workaround for LSOF check
While analysing the problem with ExaWatcher not being able to start, I found quite nasty side effect of a workaround implemented in recent versions of this useful tool. In fact, you will hit it only on Exadata X7 where you had previously implemented another workaround…
Useful Oracle tools – purgeLogs
Recently I’ve came across a nice tool provided by Oracle named purgeLogs, so I would like to shortly blog about it for reference (also for me). As the name suggests it is meant to be used for cleaning up log and trace files. Unfortunately, it…
Small fix for SQLcl Java problem with Oracle 12.1
Let’s say you want to quickly use some cool features of SQLcl inside the script running on the database server, but only Oracle below version 12.2 is available there (which is the first one being shipped with SQLcl). This means that you have to download…
Migrating from Windows to Linux with Active Duplicate for standby – problem with 11.2.0.4
Recently I was working on migrating Oracle 11.2.0.4 database running on Windows, to new hardware infrastructure on Linux. This Oracle version is with us for quite a long time, plus migration from Windows to Linux is quite common (fortunately in that direction…;)), so when I…
Oracle Unified Directory systemd unit file
About a year ago I explained in the blog post Start OUD Servers on Boot using systemd how to start Oracle Unified Directory automatically on system startup. In the meantime a lot has changed, so has my unit file. The simple unit file actually worked…
Basic Vagrantfile for multiple groups of VMs
In case you want to prepare multiple sets of machines quickly using Vagrant, ready for different setups, this might be something for you: ## -*- mode: ruby -*- ## vi: set ft=ruby : require ‚ipaddr‘ ############################### # CUSTOM CONFIGURATION START ############################### # lab_name is the…
Apache Kafka installation on Linux
In the following post, I will show how to install Apache Kafka on a Linux VM. Apache Kafka is an open-source stream processing platform developed by the Apache Software Foundation written in Scala and Java. First of all we need a Linux VM (e.g Centos 7) with…
Integrate haproxy service in MapR Control System
If you would like to create your own MapR Service under the control of warden here’s an example based on a haproxy configuration how to achieve this. The method should work for any other service as well create new role $ touch /opt/mapr/roles/haproxy create…
Preventing bash commands to be displayed in the history or deleting a specific command from history
It’s sometimes useful when using the linux command line to prevent things to go into the bash history; for example if you’re using curl to download a file while providing your username password. This can be easily done in linux by configuring the HISTCONTROL variable…
Linux change timezone and force ntpd synchronization
This short article shows how to change the timezone of the Linux distribution as well as forcing the synchronisation of date/time with the ntpd servers This applies specifically applies to CentOS so some changes might be possible depending on the distribution 1.Change timezone cp /etc/localtime…
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