Blog, Trixi

Authentication prompt while opening excel files

Posted on:
March 24, 2013
Author:
Juraj Fečanin

Last month we’ve received bug report from our customer. Web-application for this customer was created several years ago and there wasn’t any bug reported for a while. Problem was that after user logs in the app and tries to download generated excel file new credentials prompt is opened for him. After a few calls with […]

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Popis piškvorkového algoritmu

Posted on:
February 3, 2013
Author:
jh

Článek popisuje algoritmus umělé inteligence hrající piškvorky. Popsaný algoritmus si můžete vyzkoušet na stránce hratky.nenapadnymajak.cz. Algoritmus by se dal rozdělit na tři hlavní části: Procházení stromu hry -  používá se v deskových hrách velmi často používaný algoritmus alfabeta s iterativním zvětšováním hloubky stromu. Kromě alfabety se používá i podobný algoritmus MTD(f) - ten se zapojuje náhodně – aby […]

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Next stop… loading kernel modules

Posted on:
January 27, 2013
Author:
jh

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How to set up high available services – part 4

Posted on:
December 31, 2012
Author:
Juraj Fečanin

In previous part we’ve set pacemaker to work with apache, tomcat and postgresql. Only thing left to manage is database synchronization between nodes. We’ve set postgresql to run only on active node. Therefore pasive node doesn’t have data which are up to date in situation when it has to become active. There are several possibilities […]

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How to set up high available services – part 3

Posted on:
December 22, 2012
Author:
Juraj Fečanin

In this part of the High-Availability series I’ll show you how to install and configure HA software on your machines. Preconditions We assume that we have two nodes with Ubuntu 12.04.1 server preinstalled. Also there are Tomcat 7, Apache 2, Postgresql 9.1 installed on the nodes. Network settings First of all we have to set […]

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How to set up high available services – part 2

Posted on:
October 28, 2012
Author:
Juraj Fečanin

In previous post I’ve tried to explain architectural aspects of building our high available service. Today we will go through software part of the build process. After some googling I’ve found out, that there is a project which provides high availability open source software for linux. You can find software pages here. These are wiki […]

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5. pády všech jmen osob v ČR volně ke stažení

Posted on:
August 26, 2012
Author:
jh

Na stránky projektu validace.cz jsme umístili seznam všech křestních jmen a příjmení osob v ČR spolu s pátými pády. Seznam jmen pochází ze statistik, které zveřejňuje Ministerstvo vnitra. Doplněné páté pády jsou naším příspěvkem, který nabízíme volně k dispozici. Jména jsou rozdělená do několika csv souborů. V každém z nich jsou 3 sloupce: četnost jména […]

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How to set up high available services

Posted on:
August 25, 2012
Author:
Juraj Fečanin

Almost every company in the world relies on some application or applications today. If such an application fails the consequences could be various…from few unpleasant error messages which don’t influence your work to complete disaster following by thousands phone calls from angry customers. Depending on possible effects of the application failure we should prepare system […]

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Digital signatures – verification in practice

Posted on:
July 31, 2012
Author:
Jan Gargulák

We live in the 21st century, we communicate electronically and generally we don’t trust each other. Hence we need and sometimes even must use digital signatures to prove ourselves to be trustworthy. One would say there must be plenty of tools for digital signing and signature verification. Unfortunately it is not that easy. While signing […]

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Database definition management

Posted on:
June 26, 2012
Author:
Jan Gargulák

There is a lot of problems when you develop, deploy and support almost any larger applications. One of the most common problems is how to manage your (relational) database definition. By database definition I mean not only its structure (tables, constraints,..), but also certain amount of data needed for development, deployment or installation. At least […]

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