28. 01. 2019.

Easy way to create Virtualbox VM’s internal network

Virtualbox is a very popular hypervisor which allows you to run guest virtual machines like Windows, Linux, BSD, Solaris etc. For various purposes you might want to combine several virtual machines into one network. In this post I’ll describe the easiest way of how to do that, which is good enough for most of the […]

24. 01. 2019.

Installing SQL Developer on Ubuntu

Today it is not necessary to introduce SQL Developer, Oracle’s main tool to work with databases. I’ve started to use SQL Developer from the beginning (2015, project Raptor, later renamed into SQL Developer). Before that, the only Oracle tool for working with it’s flagship database was SQL*Plus (and iSQL*Plus later). For that reason, most of […]

23. 01. 2019.

Python & Oracle Instant Client connection setup on Linux – part 2

In the previous article I’ve described how to install Oracle Instant Client and setup cx_Oracle Python driver correctly. You only need Basic package to install: Version 18.3.0.0.0 Base – one of these packages is required Basic Package – All files required to run OCI, OCCI, and JDBC-OCI applications Download instantclient-basic-linux.x64-18.3.0.0.0dbru.zip (72,794,506 bytes) (cksum – 3435694482) […]

22. 01. 2019.

Python & Oracle Instant Client connection setup on Linux

In the previous post https://www.josip-pojatina.com/en/python-oracle-connection-options/ you can find how to connect to Oracle database by using cx_oracle Python driver, full Oracle Client installation and Red Hat rpm based distribution (Red Hat, CentOS, Oracle Linux, Fedora).  In reality, more than 90% of all Linux servers in a Cloud belongs to Ubuntu (unlike on premise situation where […]

18. 01. 2019.

Python – Oracle connection options

In this blog I’ll present several ways for connecting to Oracle database. As a first step To connect to Oracle database you need to import cx_oracle package. You can think of cx_oracle as Oracle jdbc driver for Java programmers. Since the first public appearance in July, 20017, Oracle is constantly improve Python cx_driver by adding […]

13. 01. 2019.

Oracle Client 18c installation on Fedora 29 Linux distribution

Fedora distribution is known as test bed for the future version of RHEL (Red Hat Enterprise Linux) distribution, is probably the best choice for Oracle DBA’s and Linux/UNIX administrators. In this post I’ll briefly explain what is needed to successfully install full Oracle client (not the Oracle Instant Client). Three things are important: 1. 64 […]

04. 01. 2019.

Multipath I/O and Network bonding

Event though Multipath I/O and NIC bonding is more related to sysadmin and storage admin tasks, it is good idea to grab some knowledge about those keywords as they play important role in achieving good performance. In the series of articles about disk speed I explained why it is good to know what values you […]

21. 12. 2018.

How to quickly check disk(s) speed limit on Linux – part 3

This is the third part of a series of articles about measuring performance of disk subsystem. In the first part you can find details of how to measure disk performance by using dd command: https://www.josip-pojatina.com/en/how-to-quickly-check-disks-speed-limits-on-linux/ while in the second part you can find similar information by using the hdparm utility: https://www.josip-pojatina.com/en/how-to-quickly-check-disks-speed-limit-on-linux-part-2/ In this blog I’ll […]

14. 12. 2018.

How to quickly check disk(s) speed limit on Linux – part 2

In the previous part of disk speed series you can see one way to test disk speed by using special options of the dd command. In this article another utility – hdparm will be described. What is common with the previous way of testing HDD disk performance is in it’s simplicity, meaning you only need […]

04. 12. 2018.

How to quickly check disk(s) speed limit on Linux

Many times I can testify that IT professionals are talking about performance without even try the most simplistic tests to find out what are the HW capabilities/limits they have. One of the first things I usually do when facing with unknown environment is to run several tests to find out how much I can get […]