Category Archives: DataCenter

#Bash one liner: Search and kill a #Java process based on a path token

By | January 15, 2020

The bash one liner of the day is to find and kill a Java process using one liner. In my case I have a Jboss application server domain that is stuck. By using jps command that displays only the running Java processes is a no brainer to kill the process by using a token that… Read More »

How to build your own mini data center @ubnt @STARTECHdotCOM

By | January 2, 2020

Moving to a new place has its advantages and disadvantage. If you are a geek, obviously you need to make a new home for your IT infrastructure 🙂 The advantage of a new location is that you get to have fun again in setting up a new mini data center. Due to some restrictions (do… Read More »

#OpenSSH private keys with old PEM format

By | December 11, 2019

Starting from openssh 7.8 the default format for private keys has changed from PEM to OpenSSH: That means that private keys generated with the referenced command: (ssh-keygen -t rsa -b 4096) are no longer generated as PEM format. Lot’s of online services do not accept this format yet CircleCI, GitHub are some of the services… Read More »

Disable core dumps in #Linux

By | December 11, 2019

Systemd doesn’t completely control whether core dumps are made or not. It mainly determine where such dumps go, and whether they should take up space or not. It may prevent some user space core dumps, but not all. With “Storage=none”, they can still occur and are registered by journald, but they don’t take up disk… Read More »

How RomArg “helped” me to change my domain register to @namecheap ?

By | December 8, 2019

A name registrar is that sort of service provider everybody needs at some point when they get serious about their online presence and want to have their own identity thus domain. Basically from the times when Internet was young their main function is to keep that record of who owns a name and to broadcast… Read More »

Remove Brother MFC 7640DN “replace drum unit” annoying message

By | December 8, 2019

Brother like any other printer producers what you do perform unnecessary costly replacements to components. We all know the lame affirmation: “quality parameters will no longer be met if producer recommendations are not followed”, but do I really need to replace the drum unit (like 80EUR) of a 200EUR printer after some 1000 pages ?… Read More »

Use #letsencrypt to generate a wildcard domain certificate

By | June 26, 2019

I am an old user of letsencrypt that just found out that my old way of renewing my set of certificated is no longer supported. When running the usual “certbot renew” command, that was manually renewing my certificates, resulted in the error: 2019-04-06 17:38:19,072:WARNING:certbot.renewal:Attempting to renew cert ( from /etc/letsencrypt/renewal/ produced an unexpected error: Client… Read More »

Convert text label files to UTF-8 encoding

By | March 28, 2019

In a lot of multi-language enterprise applications where you have to support labels in different languages the text files with the different labels for each language are scattered across your source code. In my case I all the labels are kept in Java property files with “.properties” file extension. Then for each language I have… Read More »

Migrate from #Wildfly 10 + external #ActiveMQ to #Wildfly 13 + embedded #Artemis

By | March 27, 2019

As I mentioned in a previous post I am a long time user of WildFly 10 and now in the process of upgrading to WildFly 13. Yes, not the latest version because I have some legacy source code constraints that forces me to not consider yet WildFly 14 and up. WildFly 13 includes an Artemis… Read More »

Fix #Firefox issues when load-balancing by disabling #DNS prefetching

By | March 17, 2019

There is an annoying feature from Firefox I just found out is causing me huge problems. DNS Prefetching: This feature allows firefox to try to prefetch and cache DNS entries related to the sites you visit. Firefox attempts to speed up loading new websites by using DNS Prefetching, which can cause page load errors with… Read More »