http://andriigrytsenko.net With Andrii Grytsenko Wed, 28 Jul 2010 09:02:46 +0000 http://backend.userland.com/rss092 en Here I will try to describe behavior of SW RAID level 1 in case of crash. There will be two scenario: Delete partition by fdisk and restart the computer. Delete and create empty partition by fdisk and restart the computer. Delete whole storage device from the system and restart computer. ... http://andriigrytsenko.net/2010/07/software-raid-level-1-behavior/ Here is little trick how to convert *.doc files into the *.pdf on Linux. PRE-REQUIREMENTS: oowriter has to be already installed. It is provided by Open Office system(for Debian its openoffice.org-writer package). Unfortunately, I can't remember the source where this macros is came from. Anyway here my script: #!/bin/bash # Written by Andrii Grytsenko # ... http://andriigrytsenko.net/2010/07/trick-doc-to-pdf-on-linux/ I made little overview how to make http authorization through the PERL. I'm not gonna describe how to make HTML form and how to parse input data from html. I leave these as you your homework ;). As storage for HTTP sessions I chose database(specifically MYSQL). Here is my table with ... http://andriigrytsenko.net/2010/06/perl-and-cookies-auth/ Here I systematized some of my MYSQL knowledges. First I decide to make some test database to do everything step-by-step. This will be companies database contains information about all employers, projects and departments. CREATE DATABASE company Go in: USE company And make 4 tables. Employers employer_id int primary key name varchar(15) surname varchar(25) hire_date date department_id int fired int projects project_id int primary key name varchar(255) departments department_id int primary key name varchar(255) This table consists relation between employer ... http://andriigrytsenko.net/2010/05/mysql-quick-overview/ Based on this post I have decided make some program which able to detect weather IP is a part of some network (in this case UA-IX network) or not. Speaking about UA-IX, from wikipedia we know: The Ukrainian traffic exchange network (UA-IX) (Ukrainian: Українська мережа обміну інтернет-трафіком) is an Internet exchange ... http://andriigrytsenko.net/2010/04/ua-ix-checker/ Today I decided to make my own IPCalc program. I had two reason for that. First to learn perl's binary operations and second one to make some IP calculation points more clear for me. There is some listing of my script I hope this example help you to understand some fundamental ... http://andriigrytsenko.net/2010/03/ipcalc-on-perl/ Here is short trick how to clean the shared memory up in Solaris OS. Here is short info about the host(solaris 5.9, arch sparc): uname -a SunOS hostname1 5.9 Generic_118558-25 sun4u sparc SUNW,Sun-Fire-V890 Solaris To see all shared memory segment, use ipcs user1@~>ipcs -m -a IPC status from as of Wed Mar 10 16:26:20 ... http://andriigrytsenko.net/2010/03/clean-up-the-shared-memory-in-solaris/ I'd like to describe my own experience with perl optimization. There several common way to make you code works more faster. I used perl module Benchmark to make measurements. Rules: 1. If you can use single quotes instead of double quote, do it. In most cases it will be executed more ... http://andriigrytsenko.net/2010/03/perl-performance-optimization/ Under cover you can find some trick and script to check perl module installation. To figure out whether perl module is installed at the system. Run: perl -M<module_name> -e 1 if command return an error or NOT 0(zero) then module is not installed at the moment. Here is also perl script which help you ... http://andriigrytsenko.net/2010/02/check-if-the-perl-module-is-installed/ Here is the script which check quota limits in the dbmail and in case of exceeding, script send mail to user and postmaster. Get script mail_quota.pl and mail_quota.conf configuration file at first. To make script work fine two cpan modules should be installed: cpan -i Mail::Send and cpan -i DBD::Pg This is dbmail table ... http://andriigrytsenko.net/2010/02/dbmail-mailbox-quota-notification-script/ I spent several hours to find suitable script which help me figure out my network speed between two servers. But it was fruitlessly. So, I decided to make my own script with blackjack and hoockers. (c) My Perl script require several things : Perl interpreter of course IO::Socket perl module Getopt::Long perl module I will ... http://andriigrytsenko.net/2010/02/network-bandwidth-script/ How to get online temperature status on your linux box. There is one good package which allow you to control and check your computer temperature in online mode. To install For debian: apt-get install lm-sensors for CentOS or RH: yum install lm-sensors Next software should discover all sensors in your PC, run sensors-detect: agrytsenko:~# sensors-detect ... http://andriigrytsenko.net/2010/01/get-system-temperature-in-linux/ I will show you how to use google maps to print location of your site visitors. First of all you need to get Google KEY, to do this you should have google account. If you have it visit google key page to generate the map key. After you've done it -> you ... http://andriigrytsenko.net/2010/01/google-maps-api/ Here some manual how to set up wireless usb stick(D-link dwa-110) on Debian Linux box step-by-step. First you need to get Windows drivers from your drivers CD(you can find this stuff in your modem's box). Also you need to install ndiswrapper. Put directory with drivers to /root/Drivers/ and install ndiswrapper: apt-get install ndiswrapper-common ... http://andriigrytsenko.net/2009/12/d-link-dwa-110-on-debian-box/ One of the perl debug way. Perl module PadWalker is require. Install it over cpan util: cpan -i PadWalker Let's create simple script: $cat ./hello.pl #!/usr/bin/perl sub say_hello { my $what=shift; print "Hello $what\n"; } my $var1="var1"; my $var2="var2"; say_hello("you"); my $var3="var3"; And try to debug it: $ perl -dF hello.pl Loading DB routines from perl5db.pl version 1.31 Editor support available.Enter h or `h h' ... http://andriigrytsenko.net/2009/12/perl-debug/ Recently I have faced with the next problem-> my wireless connection time-to-time became unavailable. I was starting investigation and figure out that my problem was the same as this. There is also workaround solution was found. First, let me describe my hardware and symptom data. I have usb wireless adapter D-link ... http://andriigrytsenko.net/2009/12/wireless-connection-issue/ Take this simple instruction if you need to include module (which is not installed at your system) to your perl script. Get module and install it to directory where you have write permission (For example: /home/user1/libs). Go to your script and add new library path to your INC array: use lib '/home/user1/libs'; to check ... http://andriigrytsenko.net/2009/11/use-perl-module-without-root-access/ I will try to describe how to make own home wireless access point based on RedHat linux machine. This post include 2 part. In first one I'll describe step which should be taken on linux machine and in second one step for windows client. Linux(server side) We use this host to share internet ... http://andriigrytsenko.net/2009/11/wireless-internet-ap-based-on-linux/ There is some instruction how to make centralized repository for CentOS software. As repository I have used my own Debian machine. Firstly, I have installed createrepo. This program generate some metadata which is necessary for RPM repository. Run apt-get install createrepo to install it from yum repository. Create two directories in the ... http://andriigrytsenko.net/2009/10/local-cent-os-repository-step-by-step/ Sometimes we need to reboot remote machine. But all we get an error in console. The most popular reason of this disk problems. To perform force rebooting turn on SRK feature in the kernel via proc VFS: # sysctl -w kernel.sysrq=1 and send command to kernel to reboot the system without ... http://andriigrytsenko.net/2009/10/linux-hard-reboot-and-system-request-key/