Radu Cotescu's professional blog

Why awk is better than cut

Radu — Mon, 01 Aug 2011 11:45:40 +0000

I am currently working with some text files from which I have to extract some data. Generally, when you have to do this kind of work on a *nix machine, you use cut or awk. However, even for simple tasks cut is superseded by the mighty awk. Let’s look at the following examples which are
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Bash one-liner for removing old kernel artefacts

Radu — Fri, 29 Jul 2011 13:13:57 +0000

Since now I have 4 virtual machines to administer for my dissertation project, I have to find ways to do sysadmin stuff as quickly as possible and to concentrate my efforts on software development. If you ever did a kernel update you would know that a kernel upgrade will not remove the old kernel artefacts,
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Facebook, Pidgin and the “Not authorised” error message

Radu — Wed, 15 Jun 2011 12:46:58 +0000

I noticed a few days ago that my Facebook XMPP chat account from Pidgin had stopped working, popping up a weird error message: “Not authorised”. This happened even though I did not change any of the account’s settings. The resolution is pretty Voodoo or, how Vlad described it, the error needs a Microsoft-type fix. Apparently
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Help needed

Radu — Thu, 02 Jun 2011 19:39:28 +0000

Dear all, I am running a survey for my dissertation project to collect some useful data that might help me shape the application that I am going to build. If you have previously used Ubuntu your input will be much appreciated. It shouldn’t take you more than 5 – 10 minutes to complete the form.
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How to install VMware Server on kernel version 2.6.38

Radu — Thu, 05 May 2011 11:18:56 +0000

Notices: VMware has declared VMware Server End Of Availability on January 2010 with the actual support ending on June 30th, 2011. More details can be read here. Furthermore, VMware Server is not officially supported on Ubuntu releases greater than 8.04. The VMware Server console plug-in won’t work on Firefox versions older than 3.6 (I have
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Ubuntu 64-bit and Flash videos in fullscreen

Radu — Fri, 25 Mar 2011 00:00:13 +0000

I have never been an Adobe fan and something tells me that I won’t change my mind soon. One of the main reasons for which Linux had problems being a “normal” operating system for a quite long period of time (although there were other issues as well, but not as visible at this one) was
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How to secure your SSH server from brute-force attacks

Radu — Fri, 18 Feb 2011 20:13:52 +0000

There are a lot of tutorials online that will tell you how to secure your SSH server. Most of them will tell you not to allow the root account to login, to use only keys for authentication and possibly to change the port on which your server listens from 22 to any other. Although this
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Java, HTTPS and REST web services using Apache CXF

Radu — Thu, 16 Dec 2010 23:39:23 +0000

Securing REST web services is a very debated topic on the Internet. Because REST represents an architecture, and not a protocol – like SOAP -, there aren’t any specifications dealing with security, leaving this aspect as a design decision for the software engineers / developers. Still, if you search the web to find out what
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Ubuntu and Internet Connection Sharing via a wireless card

Radu — Sat, 27 Nov 2010 18:37:46 +0000

Sharing your Internet connection is the poor man’s way of creating an access point using one of your PCs as the gateway. This implies that the PC (gateway) that you want to use for this has two network cards: an Ethernet card (NIC) connected to a network (LAN) with Internet access a wireless network interface
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How to install VMware Server on 2.6.35 kernels

Radu — Mon, 01 Nov 2010 22:37:59 +0000

Continuing the tradition of my blog this is going to be another post about VMware Server on the latest kernels provided by the most popular distributions. This is actually an example of a paradox because I don’t use this hypervisor any more, exactly due to the patching that has to be done. Still, there are
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