Posts by Tag

Simple and lightweight tabs with jQuery

A Habr user called Lzhedmitriy was not happy with the horizontal text tabs he found on the internet. As a result a simple jQuery plugin that does what he nee...

Getting HTTPS client IP addresses from HAProxy (frontend) to Nginx (backend) in HTTP and TCP balancing modes

Foreword

T-SQL cheat sheet - Part 2

A continuation of the first part:

Perl Dancer + mysql + memcached

Most of the people writing Perl have heard about the Perl Dancer micro-framework. But did they use it for anything beyond generating a project, writing a ‘He...

Blocking mail deletion in Dovecot from the mail client

An interesting task came up. I needed to make it so that even if the user has “delete messages from the server” set in the mail software - the messages still...

Debian clone, or how to make a copy of an existing Debian install

I needed to install the system on about two dozen computers. Ended up copying an already set-up system, for a few reasons: same system across all the comp...

A few useful tricks for the WordPress theme functions file

WordPress is a solid platform, offering reliable development and endless customization. Working with this CMS I picked up a few useful tricks I want to share:

A Useful Little Trick, Using the Browser Console

Some tasks get solved through the browser console (F12), with a pretty good return on effort. Still, whenever I do this, I can’t shake the feeling that I’m j...

Interesting Bash Programming Tricks

These tricks were described in Google’s internal project “Testing on the Toilet” (handing out flyers in restrooms to remind developers about testing). This p...

What grep Is and How to Use It

The other day, Habr user simpleadmin posted a pretty useful note about grep. From here on, it’s the author’s words:

Uptime in Cacti Monitoring

Cacti does get SNMP-Uptime from devices, but it only shows it on the device’s own page, and once you have more than 100 such devices, opening each page becom...

Quickly building an rpm package in CentOS with Checkinstall

To build an RPM package from an application’s source code you need Checkinstall.

Error: xz compression not available

If you get the following message while trying to install any package with yum, it means you picked the wrong repo package during install:

Useful notes about Yum

A cheat sheet for working with the Yum (Yellowdog Updater, Modified) package manager which is used in popular Linux distributions: RedHat, CentOS, Scientific...

Installing pecl on CentOS 6.5

PECL is a repository of PHP extensions. It gives you access to a catalog of all known extensions, plus tools for downloading and installing PHP extensions.

Installing PostgreSQL 9.4 on Centos 6.5

A note on how to install PostgreSQL 9.4 on Centos 6.5.

FFmpeg with libaacplus and fdk-aac support on CentOS

While working on a project for a client I needed to extend ffmpeg’s functionality and add a couple of features it doesn’t have out of the box. Needed to enab...

Setting up replication with lsync

For replicating data between servers, NFS isn’t always the right tool. If you need the same content in two directories across several servers, lsync works we...

Can’t add a service to startup on CentOS/RHEL

Ran into this while doing some routine work: couldn’t add a custom service to startup. Figured I’d write a quick note about it.

Setting up an NFS server and its clients on CentOS

NFS is quite handy when you have several servers and need shared access to the same storage from each of them. NFS lets you expose folders and files over the...

NginX and X-Forwarded-Proto:HTTPS behind a load balancer

A quick note about https traffic behind crooked load balancers. We have Setting up Nginx + php-fcgi behind a load balancer. A load balancer is like a woman -...

Mysql-Proxy: Error while loading shared libraries

If you’re reading this note, chances are you followed some random mysql-proxy install guide.

Getting HTTPS client IP addresses from HAProxy (frontend) to Nginx (backend) in HTTP and TCP balancing modes

Foreword

Install Mysql-Proxy into RedHat 6.4

While working with CentOS I had no issues to install Mysql-Proxy but with RedHad 6.4 this approach didn’t work. Here is why I made a second version on how to...

Stats for NginX Upstream

When using NginX as a load balancer, the question comes up of how to properly track traffic delivery stats for the servers in the Upstream section.

HaProxy configuration examples

Following up on the first article, in this one I want to look at a few examples of configuring HaProxy for balancing traffic.

Mysql-Proxy: installing and configuring on CentOS7

Balancing mysql queries matters if you’re running several mysql servers. If you’ve got master-slave replication set up, it makes sense to spread the load acr...

Load balancing with NginX

Hello, dear reader. In this article I want to describe how to set up NginX for load balancing across several back-end servers, say Apache.

Get Inique IP addresses from Apache access.log

The following can be used to fetch the unique records from apache access.log. This example covers IP addresses of the clients but this example can be used to...

Upgrading Apache 2.2.31 OpenSSL 1.0.1q on CentOS 6.7

In recent times, I’ve increasingly encountered the need to update OpenSSL to its latest version on servers. Unfortunately, so much relies on the OpenSSL libr...

Load Balancing with Apache

Greetings dear reader. In this article I want to describe how to configure Apache to load balance multiple back-end servers. You’ll need the following two mo...

How to Compile php v.5.5.10 from Sources

This note covers how to install the latest version of PHP on your server from source, using PHP 5.5.10 + CentOS 6.5 as an example.

Building a secure web server

To create the most secure web server we need the following: Create a sandbox chroot with debootstrap sandbox apache2, php5, mysql install and configur...

Writing Custom Check Modules for Nagios Using mysql and apache2 as Examples

Nagios is an open-source client-server platform for monitoring computer systems and networks. It’s built for observing and tracking the state of compute node...

Configuring Awstats for Apache

Awstats is a free log analyzer written in Perl. It lets you build nice visit report graphs for your site based on info from log files.

Configuring Postfix Mail Forwarding Domains

Introduction Configuring Postfix mail forwarding domains is a practical solution for situations where local mailboxes are not available, and the server is no...

Postfix change sender domain

Out of the box postfix is sending emails using the domain name that is returned by the following command in the linux shell: uname -n

Use DKIM signature for outgoing emails

Email spoofing is the creation of email messages with a forged sender address. There are many services that provide protection from spoofing.

Configuring Postfix to send mail through MailGun

This article is about how to configure your Linux server to send mail through the MailGun service.

How to find the script that is spamming via postfix

If you find that your postfix server keeps sending and you understand that you have been scammed. Pretty disgusting state of affairs.

Installing and configuring Postfix

This article opens a series of articles about setting up a mail server. The whole story starts with the configuration of the so called mail transfer agent (M...

Postfix: change the sender address

If your server sends out mail and you don’t want the messages to be delivered from [email protected], then you can change the sender address.

Installing NewRelic Plugins with NPI: MySQL Example

Most people know newrelic.com - a service for tracking application state and performance. This service is developing pretty fast and the developers keep expa...

Index in MySQL tables

To create a unique index for a MySQL table, run this command:

Setting up a Linux server for WordPress/Drupal/Joomla

This is a practical guide to setting up a server for maximum performance running one of the blog-oriented CMS platforms: WordPress, Drupal, or Joomla.

Installing and configuring an imap/pop3 service based on Dovecot

This is the second article of the series about a mail server based on CentOS Linux. It is about how to give people access to their incoming mail over imap/po...

Bash Script for Backing Up and Restoring All MySQL Databases and Users

This note is about how to quickly dump all MySQL databases into separate files from bash: Backup:

Writing Custom Check Modules for Nagios Using mysql and apache2 as Examples

Nagios is an open-source client-server platform for monitoring computer systems and networks. It’s built for observing and tracking the state of compute node...

Importing posts from WordPress into Yii

Riding the wave of the previous post, I decided to play around with Yii and try porting this site, posts and pages included, over to Yii.

Setting up a Linux server for WordPress/Drupal/Joomla

This is a practical guide to setting up a server for maximum performance running one of the blog-oriented CMS platforms: WordPress, Drupal, or Joomla.

Showing phpinfo output on a WordPress page without FTP access to the server

If you’ve run into the same problem I did, welcome. Someone reached out saying everything's gone. No server access, logins and passwords all changed. Need to...

Contact form for WordPress website without additional plugins

There are different plugins that enable contact form for WordPress websites. For some reason none of them worked correctly on my blog. Knowing some basic Wor...

IIS, PHP, OpenSource CMS and rabbits

Personally I consider hosting open-source projects on Windows Server a sacrilege, a stupidity and a moral defect. But sometimes there is a project where the ...

How to configure Exim to use SendGrid to send mail

I continue my series of articles about email services until the inspiration from the recently solved problems wears off.

WHM (cPanel): How to Kill a Stuck Transfer

Had to move accounts between servers today. Naturally used the WHM Transfer tool. One of the batches got stuck mid-process. Unfortunately the developers didn...

Using cPanel (WHM) to Manage a Cluster

WHM is a decent server management tool. It’s paid, but the developers did a solid job. It’s fairly common to install WHM/cPanel on a single server that holds...

Bypassing WHM/cPanel Security Questions

Doing match calculations in BASH with bc

bc is a tool that allows to do inline calculations in bash cli. Eventually bc can’t be used for complicated calculations.

Listing installed packages in Linux

You can get the list of installed packages in Ubuntu Linux with this command:

Skype4py Script for Sending Skype Messages from the Linux Ubuntu Console

A short note on how to make Bash scripts send messages to Skype.

Quick and Dirty Website Monitoring (bash script)

Because of the nature of my work I deal with a lot of websites. Given the specifics of these projects, I sometimes need to keep an eye on web resource availa...

Setting up a Linux server for WordPress/Drupal/Joomla

This is a practical guide to setting up a server for maximum performance running one of the blog-oriented CMS platforms: WordPress, Drupal, or Joomla.

Installing Asp.Net on Linux (nginx+mono+xsp)

In this article I’ll show how to set up a simple nginx + Asp.Net combo. By simple I mean that project-specific quirks, user permission separation, high load ...

Load balancing with NginX

Hello, dear reader. In this article I want to describe how to set up NginX for load balancing across several back-end servers, say Apache.

Setting up Nginx + php-fcgi

I assume nginx is already installed. What’s left is to set up php handling. Everything below was done on CentOS Linux. You can repeat the same steps on Linux...

Securing Weak Points in Apache SSL Configuration

Vulnerabilities are occasionally found in the SSL protocol, which enables encrypted traffic exchange between a server and a client. These vulnerabilities pot...

Upgrading Apache 2.2.31 OpenSSL 1.0.1q on CentOS 6.7

In recent times, I’ve increasingly encountered the need to update OpenSSL to its latest version on servers. Unfortunately, so much relies on the OpenSSL libr...

NginX and X-Forwarded-Proto:HTTPS behind a load balancer

A quick note about https traffic behind crooked load balancers. We have Setting up Nginx + php-fcgi behind a load balancer. A load balancer is like a woman -...

Simulate https (ssl) session using the rewrite module

In this article I want to touch on the topic of load balancing https connections.

List items should be accessed using square brackets

This is a note about the following error that is produced by tflint Warning: List items should be accessed using square brackets (terraform_deprecated_index)...

Use gitlab to store terraform state file

This is a short note about the way to configure your GitlabCI to store the Terraform state file. Terraform backend configuration remains pretty simple: terra...

More examples with terraform for and for_each loops

Loops in terraform is not something new. There is a bunch of articles with examples in the internet. However I had a number of cases when I could not find th...

Use bash script as data source in terrafform

I was for a multiple times when I had to extract some data with bash script and next re-use the result in terraform resource provisioning. I’d like to share ...

How to Run Multiple Skype Instances in Ubuntu

In this note I want to show how you can run several Skype processes in Linux Ubuntu. I have 2 running - work and personal.

Skype4py Script for Sending Skype Messages from the Linux Ubuntu Console

A short note on how to make Bash scripts send messages to Skype.

Skype4py Script for Sending Skype Messages from the Linux Ubuntu Console

A short note on how to make Bash scripts send messages to Skype.

Daily statistics in AwStats

AwStats is a log file parser written in perl, with which you can keep statistics of site visits based on information from log files. As a rule, awstats disp...

Configuring Awstats for Nginx

In this post I want to go over an example of how to get Awstats working correctly with Nginx server log files.

Configuring Awstats for Apache

Awstats is a free log analyzer written in Perl. It lets you build nice visit report graphs for your site based on info from log files.

Displaying ServerVariables in IIS

A lot of admins use the phpinfo function to debug the headers the server gets when the site is requested.

Configuring ETags in IIS7

Entity tags (ETags) are the mechanism web servers and browsers use to determine whether an element in the browser cache matches the object on the server.

IIS, PHP, OpenSource CMS and rabbits

Personally I consider hosting open-source projects on Windows Server a sacrilege, a stupidity and a moral defect. But sometimes there is a project where the ...

Forward requests over Apache with ProxyPass

For various reasons you may want to display information from one server to another. I won’t go into the reasons.

Load Balancing with Apache

Greetings dear reader. In this article I want to describe how to configure Apache to load balance multiple back-end servers. You’ll need the following two mo...

Load balancing with NginX

Hello, dear reader. In this article I want to describe how to set up NginX for load balancing across several back-end servers, say Apache.

Setting up a Linux server for WordPress/Drupal/Joomla

This is a practical guide to setting up a server for maximum performance running one of the blog-oriented CMS platforms: WordPress, Drupal, or Joomla.

Adding an item to the components menu in the Joomla! admin

After a failed update of a plugin, or any other Joomla! component, an unpleasant situation happens - the icon disappears from the menu. You can easily bring ...

How to make Search Engine Friendly (SEF) URLs work in Joomla! on Nginx

Search engine friendly (SEF) URLs are the links to the articles of your site in a form that is easy on the eye. They at least partially show what the post on...

Useful notes about Yum

A cheat sheet for working with the Yum (Yellowdog Updater, Modified) package manager which is used in popular Linux distributions: RedHat, CentOS, Scientific...

Removing an application and its dependencies on CentOS/RHEL

By default yum remove only removes the package you specify. To also remove everything that got installed along with it, use the yum-plugin-remove-with-leaves...

Listing installed packages in Linux

You can get the list of installed packages in Ubuntu Linux with this command:

Removing Extra Spaces from Strings in Microsoft Jscript

MS Jscript has a ton of functions and methods borrowed from VisualBasic and Microsoft C/C++. Among them is the trim function, which lets you strip extra spac...

Counting DNS Zones in Windows Server 2008/2012 with Microsoft Jscript

Once I had to automate the process of getting info about the DNS zones sitting on some abstract Windows server. Again it cuts at my brain that I’m writing a ...

Passing Data from Windows CMD to Microsoft Jscript

Ran into another one: I need to get a set of data about the server using Microsoft Jscript. Tripping over Windows 2008 Server quirks again. It’s just really ...

Mysql-Proxy: Error while loading shared libraries

If you’re reading this note, chances are you followed some random mysql-proxy install guide.

Install Mysql-Proxy into RedHat 6.4

While working with CentOS I had no issues to install Mysql-Proxy but with RedHad 6.4 this approach didn’t work. Here is why I made a second version on how to...

Mysql-Proxy: installing and configuring on CentOS7

Balancing mysql queries matters if you’re running several mysql servers. If you’ve got master-slave replication set up, it makes sense to spread the load acr...

Refresh Jenkins job properties

Refresh Jenkins job properties

Cheatsheet for Groovy to be used in Jenkins pipelines

Cheatsheet for Groovy to be used in Jenkins pipelines

Parrallel stages in Jenkins Groovy pipeline

Parrallel stages in Jenkins Groovy pipeline

WHM (cPanel): How to Kill a Stuck Transfer

Had to move accounts between servers today. Naturally used the WHM Transfer tool. One of the batches got stuck mid-process. Unfortunately the developers didn...

Bypassing WHM/cPanel Security Questions

Get Inique IP addresses from Apache access.log

The following can be used to fetch the unique records from apache access.log. This example covers IP addresses of the clients but this example can be used to...

Configuring Awstats for Nginx

In this post I want to go over an example of how to get Awstats working correctly with Nginx server log files.

Launching a Terminal with Multiple Tabs in Linux Ubuntu

A short note on how to launch a terminal with multiple tabs in Linux Ubuntu:

Launching a Terminal with Multiple Tabs in Linux Ubuntu

A short note on how to launch a terminal with multiple tabs in Linux Ubuntu:

How to Enable Hibernate on Linux Ubuntu

On some laptops, after installing Linux Ubuntu (12.04 LTS in my case), hibernate is disabled. Looks like it’s because such devices aren’t officially supporte...

Launching a Terminal with Multiple Tabs in Linux Ubuntu

A short note on how to launch a terminal with multiple tabs in Linux Ubuntu:

Upgrading Apache 2.2.31 OpenSSL 1.0.1q on CentOS 6.7

In recent times, I’ve increasingly encountered the need to update OpenSSL to its latest version on servers. Unfortunately, so much relies on the OpenSSL libr...

A tale of installing OpenSSH 6 from source on a remote CentOS 5.8 server

Everyone knows how conservative RedHat and CentOS are about updating packages. But new security holes keep turning up in old software versions, and that’s no...

Create SSL certificate in Linux.

In continuation of the series of articles about SSL I would like to describe the steps for the appearance of certificates. I will not repeat the terminology....

Fail2Ban configuration

Fail2Ban is a software written in Python which is designed to prevent attacks on the server. It reads ssh, ftp, apache log files and blocks ip addresses by a...

Tunning fail2ban in Plesk

Plesk allows to tune configuration of almost everything. fail2ban configuration is locates on the page Tools & Settings. Locate the section of IP Address...

Fail2Ban configuration

Fail2Ban is a software written in Python which is designed to prevent attacks on the server. It reads ssh, ftp, apache log files and blocks ip addresses by a...

Setting up a Linux server for WordPress/Drupal/Joomla

This is a practical guide to setting up a server for maximum performance running one of the blog-oriented CMS platforms: WordPress, Drupal, or Joomla.

IIS, PHP, OpenSource CMS and rabbits

Personally I consider hosting open-source projects on Windows Server a sacrilege, a stupidity and a moral defect. But sometimes there is a project where the ...

Configure SFTP Chroot at Ubuntu 14.04

This article covers setting up an sftp server and isolating users in their home directories (chroot) based on Linux Ubuntu 14.04.

Building a secure web server

To create the most secure web server we need the following: Create a sandbox chroot with debootstrap sandbox apache2, php5, mysql install and configur...

List of ColdFusion DataSources Usernames and Passwords

In ColdFusion settings, database connections can be configured in the admin panel under the DataSources section. But what do you do if the passwords for seve...

404 errors in ColdFusion10

After the move from an IIS6+ColdFusion8 server to a server with IIS7+Coldfusion10 I did not enjoy the fact that all the start pages of the sites open for ver...

Installing php-mcrypt on CentOS 6

To install php-mcrypt on CentOS Linux you need to enable a couple extra repos first:

Postfix: change the sender address

If your server sends out mail and you don’t want the messages to be delivered from [email protected], then you can change the sender address.

IP Address Pool Error in Plesk

Sometimes when working with Plesk version 10 you get an ip address pool error:

Plesk: Viewing All Mailboxes on the Server

First connect to mysql: mysql -uadmin -p`cat /etc/psa/.psa.shadow` psa

Blocking mail deletion in Dovecot from the mail client

An interesting task came up. I needed to make it so that even if the user has “delete messages from the server” set in the mail software - the messages still...

Installing and configuring an imap/pop3 service based on Dovecot

This is the second article of the series about a mail server based on CentOS Linux. It is about how to give people access to their incoming mail over imap/po...

Copying a Parallels Virtuozzo container to a new hypervisor

In this note I want to cover how to copy/migrate a Parallels Virtuozzo container to KVM/VMware ESX/VirtualBox.

Converting a Parallels Virtuozzo container into a Parallels Bare Metal Server VM

Virtuozzo and Bare Metal Server are two commercial virtualization products from Parallels. They use different approaches to storing VM data.

Automating Database Transfers Between MSSQL 2008 Servers

Spitting on Windows server projects again. The other day I ran into a task - needed to move a few hundred databases from one server to another.

Making a Backup of All Databases in MSSQL Server 2008

Sometimes you need to make a one-off backup of all databases (all databases) so you can move them somewhere or gather them in a separate storage location.

T-SQL cheat sheet - Part 2

A continuation of the first part:

Automating Database Transfers Between MSSQL 2008 Servers

Spitting on Windows server projects again. The other day I ran into a task - needed to move a few hundred databases from one server to another.

Disable Diffie-Hellman Modulus vsFTPD

I couldn’t find how to disable Diffie-Hellman encryption in vsFTPD TLS.

Using virtual users in Vsftpd

This post will show you how to create virtual users in vsftpd.

Making a backup of all the databases in MSSQL 2008/2012

To make backup copies of all the databases on your MSSQL 2008/2012 server you can use the following SQL query:

Backup webiste to Dropbox

The other day I was wondering about the correct backup of several WordPress sites and then uploading them to some free storage. I would like it to be done wi...

The HaProxy statistics page

HaProxy provides a convenient tool for showing statistics in real time.

A short overview of what HaProxy can do

HaProxy is a wonderful and very flexible tool for balancing traffic. It has a whole pile of options and configuration variants, and it has its own quirks. It...

AdSense in a dynamic WordPress sidebar

I’ve had an AdSense block sitting in my sidebar for a while now. It only recently occurred to me that the sidebar has a dynamic size (22% of the page body), ...

Add an AdSense block to a WordPress sidebar

Adsense is probably the most common contextual ad service out there. For WordPress there’s a whole bunch of plugins for installing the ad code.

Switching PHP to CGI mode for a specific folder.

Recently, I came across an issue: phpMyAdmin was complaining about the absence of the mcrypt module in PHP. The strange thing was that when I ran php -m in t...

Configure suexec for Apache2 on Ubuntu 14.04

The suexec mechanism allows you to execute CGI scripts on behalf of different system users. In this article, I’ll walk through an example of setting up suexe...

Jenkins auth over AWS Cognito

Jenkins auth over AWS Cognito

Copy the Jenkins job

Copy the Jenkins job

AWS account structure for a startup after Series A

Same story as the GCP version of this note, different cloud: startup closes Series A, and the AWS side is still one root user, one account, prod and the sand...

GCP organization and folder structure for a startup after Series A

Recently I had a case where a startup closed their Series A and was still running everything out of one GCP project tied to the founder’s personal Google acc...

AWS account structure for a startup after Series A

Same story as the GCP version of this note, different cloud: startup closes Series A, and the AWS side is still one root user, one account, prod and the sand...

GCP organization and folder structure for a startup after Series A

Recently I had a case where a startup closed their Series A and was still running everything out of one GCP project tied to the founder’s personal Google acc...

Displaying database size in PostgreSQL

I already have a note on checking database size in MySQL, here is the same for psql.

psql command line cheat sheet

I switch between MySQL and PostgreSQL often enough that the psql meta-commands never stick in my head. Every time it’s the same five minutes of googling \d v...

Displaying database size in PostgreSQL

I already have a note on checking database size in MySQL, here is the same for psql.

psql command line cheat sheet

I switch between MySQL and PostgreSQL often enough that the psql meta-commands never stick in my head. Every time it’s the same five minutes of googling \d v...

View all FTP accounts created in Plesk on a Linux server via mysql

It happens that the Plesk WebUI becomes unavailable for any reason. Or we have a set of files from the old server and we need to restore all ftp users on the...

View all FTP accounts created in Plesk on a Linux server via mysql

It happens that the Plesk WebUI becomes unavailable for any reason. Or we have a set of files from the old server and we need to restore all ftp users on the...

Skype4py Script for Sending Skype Messages from the Linux Ubuntu Console

A short note on how to make Bash scripts send messages to Skype.

Skype4py Script for Sending Skype Messages from the Linux Ubuntu Console

A short note on how to make Bash scripts send messages to Skype.

Skype4py Script for Sending Skype Messages from the Linux Ubuntu Console

A short note on how to make Bash scripts send messages to Skype.

Configuring Awstats for Apache

Awstats is a free log analyzer written in Perl. It lets you build nice visit report graphs for your site based on info from log files.

Configuring Awstats for Apache

Awstats is a free log analyzer written in Perl. It lets you build nice visit report graphs for your site based on info from log files.

A problem starting Squid

I hit a problem with starting Squid on RedHat Linux v.6.4. Squid just did not start.

Moving SmarterMail to a new server

At any moment, for one reason or another, the question of moving SmarterMail to a new server can come up. The reasons can be different and I am not going to ...

Moving SmarterMail to a new server

At any moment, for one reason or another, the question of moving SmarterMail to a new server can come up. The reasons can be different and I am not going to ...

Setting up Nginx + php-fcgi

I assume nginx is already installed. What’s left is to set up php handling. Everything below was done on CentOS Linux. You can repeat the same steps on Linux...

GeoIP for Nginx

The GeoIP module lets you determine a client’s location based on their IP address. It resolves city, region, country, longitude, latitude, and other info. Ve...

Launching a Terminal with Multiple Tabs in Linux Ubuntu

A short note on how to launch a terminal with multiple tabs in Linux Ubuntu:

Writing Custom Check Modules for Nagios Using mysql and apache2 as Examples

Nagios is an open-source client-server platform for monitoring computer systems and networks. It’s built for observing and tracking the state of compute node...

A tale of installing OpenSSH 6 from source on a remote CentOS 5.8 server

Everyone knows how conservative RedHat and CentOS are about updating packages. But new security holes keep turning up in old software versions, and that’s no...

A tale of installing OpenSSH 6 from source on a remote CentOS 5.8 server

Everyone knows how conservative RedHat and CentOS are about updating packages. But new security holes keep turning up in old software versions, and that’s no...

Magento: remove trailing slash from the website URL

A note on how to remove the slash at the end of the URL without damaging the store.

Magento: remove trailing slash from the website URL

A note on how to remove the slash at the end of the URL without damaging the store.

How to Enable Hibernate on Linux Ubuntu

On some laptops, after installing Linux Ubuntu (12.04 LTS in my case), hibernate is disabled. Looks like it’s because such devices aren’t officially supporte...

How to Enable Hibernate on Linux Ubuntu

On some laptops, after installing Linux Ubuntu (12.04 LTS in my case), hibernate is disabled. Looks like it’s because such devices aren’t officially supporte...

Sendmail is not accepting incoming connections

Found the following error in the logs and decided to write a note about it:

Security tunning of SSH server

SSH is a secure terminal server (secure shell) that provides remote access to the linux system. Why safe? Because all traffic between the client and the serv...

Security tunning of SSH server

SSH is a secure terminal server (secure shell) that provides remote access to the linux system. Why safe? Because all traffic between the client and the serv...

Security tunning of SSH server

SSH is a secure terminal server (secure shell) that provides remote access to the linux system. Why safe? Because all traffic between the client and the serv...

How to create an admin user in Joomla with mysql

Sometimes you badly need to get into the admin panel of the Joomla CMS, but there is no information about the users that were already created. At the same ti...

Setting up an NFS server and its clients on CentOS

NFS is quite handy when you have several servers and need shared access to the same storage from each of them. NFS lets you expose folders and files over the...

Using a custom ssh port for rsync

Rsync is a handy tool for syncing data between servers.

Using a custom ssh port for rsync

Rsync is a handy tool for syncing data between servers.

IIS, PHP, OpenSource CMS and rabbits

Personally I consider hosting open-source projects on Windows Server a sacrilege, a stupidity and a moral defect. But sometimes there is a project where the ...

IIS, PHP, OpenSource CMS and rabbits

Personally I consider hosting open-source projects on Windows Server a sacrilege, a stupidity and a moral defect. But sometimes there is a project where the ...

IIS, PHP, OpenSource CMS and rabbits

Personally I consider hosting open-source projects on Windows Server a sacrilege, a stupidity and a moral defect. But sometimes there is a project where the ...

IIS, PHP, OpenSource CMS and rabbits

Personally I consider hosting open-source projects on Windows Server a sacrilege, a stupidity and a moral defect. But sometimes there is a project where the ...

Out of memory on a WordPress server, or what to do about php memory_limit

Today, logging into the blog admin, I got this error:

Out of memory on a WordPress server, or what to do about php memory_limit

Today, logging into the blog admin, I got this error:

Out of memory on a WordPress server, or what to do about php memory_limit

Today, logging into the blog admin, I got this error:

.htaccess tips and tricks

I’d like to present a set of interesting and not very features of .htaccess files and what can be done with them. Most of what is described here falls into t...

.htaccess tips and tricks

I’d like to present a set of interesting and not very features of .htaccess files and what can be done with them. Most of what is described here falls into t...

.htaccess tips and tricks

I’d like to present a set of interesting and not very features of .htaccess files and what can be done with them. Most of what is described here falls into t...

Purging the Varnish cache from the browser with PHP

In this note I want to show how to purge the Varnish cache in an elegant way. The article describes how to delete pages=objects from the cache using their UR...

Purging the Varnish cache from the browser with PHP

In this note I want to show how to purge the Varnish cache in an elegant way. The article describes how to delete pages=objects from the cache using their UR...

Purging the Varnish cache from the browser with PHP

In this note I want to show how to purge the Varnish cache in an elegant way. The article describes how to delete pages=objects from the cache using their UR...

Building a secure web server

To create the most secure web server we need the following: Create a sandbox chroot with debootstrap sandbox apache2, php5, mysql install and configur...

Installing the Plesk Migration Manager

To install additional Plesk components you can use this utility: /usr/local/psa/admin/bin/autoinstaller

Installing the Plesk Migration Manager

To install additional Plesk components you can use this utility: /usr/local/psa/admin/bin/autoinstaller

How to Compile php v.5.5.10 from Sources

This note covers how to install the latest version of PHP on your server from source, using PHP 5.5.10 + CentOS 6.5 as an example.

Problem uploading files over php forms in Apache

Today I encountered the problem of uploading files that clearly do not exceed the post_max_size and upload_max_filesize limits. The following error appears: ...

How to make Search Engine Friendly (SEF) URLs work in Joomla! on Nginx

Search engine friendly (SEF) URLs are the links to the articles of your site in a form that is easy on the eye. They at least partially show what the post on...

How to make Search Engine Friendly (SEF) URLs work in Joomla! on Nginx

Search engine friendly (SEF) URLs are the links to the articles of your site in a form that is easy on the eye. They at least partially show what the post on...

How to make Search Engine Friendly (SEF) URLs work in Joomla! on Nginx

Search engine friendly (SEF) URLs are the links to the articles of your site in a form that is easy on the eye. They at least partially show what the post on...

How to Run Multiple Skype Instances in Ubuntu

In this note I want to show how you can run several Skype processes in Linux Ubuntu. I have 2 running - work and personal.

How to Run Multiple Skype Instances in Ubuntu

In this note I want to show how you can run several Skype processes in Linux Ubuntu. I have 2 running - work and personal.

How to Run Multiple Skype Instances in Ubuntu

In this note I want to show how you can run several Skype processes in Linux Ubuntu. I have 2 running - work and personal.

osCommerce Language File Issue

Working with an osCommerce shop, I periodically hit a ‘503 Server Error’.

osCommerce Language File Issue

Working with an osCommerce shop, I periodically hit a ‘503 Server Error’.

Error: database disk image is malformed

To make yum work again in CentOS after this error:

Installing whm/cpanel and Using a Remote MySQL Server

Got a task: install WHM/cPanel on a server. Sounds simple enough, except there are two servers involved: 1 - web server. 2 - MySQL database server.

Installing whm/cpanel and Using a Remote MySQL Server

Got a task: install WHM/cPanel on a server. Sounds simple enough, except there are two servers involved: 1 - web server. 2 - MySQL database server.

404 errors in ColdFusion10

After the move from an IIS6+ColdFusion8 server to a server with IIS7+Coldfusion10 I did not enjoy the fact that all the start pages of the sites open for ver...

Sending mail with telnet to an smtp server

Telnet is a nice utility that lets you open a network connection to any service by specifying the port to connect to. Telnet is part of the standard set of u...

Sending mail with telnet to an smtp server

Telnet is a nice utility that lets you open a network connection to any service by specifying the port to connect to. Telnet is part of the standard set of u...

Installing Asp.Net on Linux (nginx+mono+xsp)

In this article I’ll show how to set up a simple nginx + Asp.Net combo. By simple I mean that project-specific quirks, user permission separation, high load ...

Installing Asp.Net on Linux (nginx+mono+xsp)

In this article I’ll show how to set up a simple nginx + Asp.Net combo. By simple I mean that project-specific quirks, user permission separation, high load ...

Installing Asp.Net on Linux (nginx+mono+xsp)

In this article I’ll show how to set up a simple nginx + Asp.Net combo. By simple I mean that project-specific quirks, user permission separation, high load ...

Adding an item to the components menu in the Joomla! admin

After a failed update of a plugin, or any other Joomla! component, an unpleasant situation happens - the icon disappears from the menu. You can easily bring ...

Adding an item to the components menu in the Joomla! admin

After a failed update of a plugin, or any other Joomla! component, an unpleasant situation happens - the icon disappears from the menu. You can easily bring ...

Installing Drush by Hand

Drush is a cli for Drupal. In this article I’ll cover how to install it without pear. I won’t go into details on that.

Installing Drush by Hand

Drush is a cli for Drupal. In this article I’ll cover how to install it without pear. I won’t go into details on that.

Postfix: change the sender address

If your server sends out mail and you don’t want the messages to be delivered from [email protected], then you can change the sender address.

Bash: Extracting the Configuration of a Single Apache Virtual Host

Starting a series of posts with interesting Bash puzzles.

Bash: Extracting the Configuration of a Single Apache Virtual Host

Starting a series of posts with interesting Bash puzzles.

Configure ClamAV to scan files uploaded via FTP (PureFTPd)

In this note I want to tell you how to configure the ClamAV antivirus to scan files that are uploaded to the server via PureFTPD.

Configure ClamAV to scan files uploaded via FTP (PureFTPd)

In this note I want to tell you how to configure the ClamAV antivirus to scan files that are uploaded to the server via PureFTPD.

Listing installed packages in Linux

You can get the list of installed packages in Ubuntu Linux with this command:

Simulate https (ssl) session using the rewrite module

In this article I want to touch on the topic of load balancing https connections.

Install Apache Passenger for Ruby

A small note on how to install Apache passenger on CentOS to work with Ruby. I assume you have the following packages installed: ruby-mysql rubygems r...

Install Apache Passenger for Ruby

A small note on how to install Apache passenger on CentOS to work with Ruby. I assume you have the following packages installed: ruby-mysql rubygems r...

Uptime in Cacti Monitoring

Cacti does get SNMP-Uptime from devices, but it only shows it on the device’s own page, and once you have more than 100 such devices, opening each page becom...

Uptime in Cacti Monitoring

Cacti does get SNMP-Uptime from devices, but it only shows it on the device’s own page, and once you have more than 100 such devices, opening each page becom...

Moving mail from one server to another with Larch

Larch is a utility written in ruby that can be very useful when moving mail from one mail service to another.

Internal Zend error wp-cache-base.php

If you’re seeing this error on your WordPress blog:

Internal Zend error wp-cache-base.php

If you’re seeing this error on your WordPress blog:

Installing Ruby 1.9.3 on RedHat 6

Ruby 1.9 isn’t available through yum on Red Hat Enterprise Linux 6, per this page: https://access.redhat.com/site/solutions/131923

Installing Ruby 1.9.3 on RedHat 6

Ruby 1.9 isn’t available through yum on Red Hat Enterprise Linux 6, per this page: https://access.redhat.com/site/solutions/131923

Installing Ruby 1.9.3 on RedHat 6

Ruby 1.9 isn’t available through yum on Red Hat Enterprise Linux 6, per this page: https://access.redhat.com/site/solutions/131923

Installing ionCube Loader for PHP

ionCube Loader is needed to run paid components on your server that the site relies on. Such components usually have obfuscated code, which makes them unread...

Installing ionCube Loader for PHP

ionCube Loader is needed to run paid components on your server that the site relies on. Such components usually have obfuscated code, which makes them unread...

Configuring parallel mail delivery (Dual Delivery) in Postfix

This note tells how to use Postfix to organize parallel delivery of mail to several mail servers within one domain name, without the well known forwarding or...

Configuring parallel mail delivery (Dual Delivery) in Postfix

This note tells how to use Postfix to organize parallel delivery of mail to several mail servers within one domain name, without the well known forwarding or...

Configuring parallel mail delivery (Dual Delivery) in Postfix

This note tells how to use Postfix to organize parallel delivery of mail to several mail servers within one domain name, without the well known forwarding or...

Configuring parallel mail delivery (Dual Delivery) in Postfix

This note tells how to use Postfix to organize parallel delivery of mail to several mail servers within one domain name, without the well known forwarding or...

Installing PostfixAdmin and RoundCube

This note tells how to install the mailbox management tool - PostfixAdmin, and a convenient interface for reading mail - RoundCube, on a server running CentO...

Installing PostfixAdmin and RoundCube

This note tells how to install the mailbox management tool - PostfixAdmin, and a convenient interface for reading mail - RoundCube, on a server running CentO...

Installing and configuring Postfix

This article opens a series of articles about setting up a mail server. The whole story starts with the configuration of the so called mail transfer agent (M...

Forward requests over Apache with ProxyPass

For various reasons you may want to display information from one server to another. I won’t go into the reasons.

Install modsecurity for Nginx

ModSecurity is a kind of firewall for Apache, Nginx and IIS. This is a module that provides a set of rules for filtering traffic. This is a must have module ...

IP Address Pool Error in Plesk

Sometimes when working with Plesk version 10 you get an ip address pool error:

Contact form for WordPress website without additional plugins

There are different plugins that enable contact form for WordPress websites. For some reason none of them worked correctly on my blog. Knowing some basic Wor...

Showing phpinfo output on a WordPress page without FTP access to the server

If you’ve run into the same problem I did, welcome. Someone reached out saying everything's gone. No server access, logins and passwords all changed. Need to...

Interesting Bash Programming Tricks

These tricks were described in Google’s internal project “Testing on the Toilet” (handing out flyers in restrooms to remind developers about testing). This p...

Create SSL certificate in Linux.

In continuation of the series of articles about SSL I would like to describe the steps for the appearance of certificates. I will not repeat the terminology....

Create SSL certificate in Linux.

In continuation of the series of articles about SSL I would like to describe the steps for the appearance of certificates. I will not repeat the terminology....

Create SSL certificate in Linux.

In continuation of the series of articles about SSL I would like to describe the steps for the appearance of certificates. I will not repeat the terminology....

Create SSL certificate in Linux.

In continuation of the series of articles about SSL I would like to describe the steps for the appearance of certificates. I will not repeat the terminology....

Create SSL certificate in Linux.

In continuation of the series of articles about SSL I would like to describe the steps for the appearance of certificates. I will not repeat the terminology....

Create SSL certificate in Linux.

In continuation of the series of articles about SSL I would like to describe the steps for the appearance of certificates. I will not repeat the terminology....

How to edit the Meta widget in WordPress

Whether a site needs user registration is a question that sparks a lot of debate.

Package Installation Issues in Ubuntu 12.04

Even though Ubuntu 12.04 shipped with the LTS (long term support) label, looks like that long term is over. A lot of people have already run into problems in...

Usage of lftp to work with files on ftp server from Linux

lftp is a command line utility that allows you to exchange data with ftp and http servers. lftp has mirroring functionality that allows you to load or recurs...

How I Load Tested Moodle

I got a task: check how many concurrent users a moodle-based site can handle.

How I Load Tested Moodle

I got a task: check how many concurrent users a moodle-based site can handle.

Magento Got Stuck on Data Reindexing

Someone reached out to me asking to check what’s wrong with their site. Said it wasn’t working.

Installing Munin on CentOS

Munin is a tool for monitoring network devices with the ability to keep a history of their performance. You can view the performance graphs in a browser.

Installing Munin on CentOS

Munin is a tool for monitoring network devices with the ability to keep a history of their performance. You can view the performance graphs in a browser.

MySQL: setting up replication

OK. This isn’t an original article. There’s plenty like it on the internet already. I need it so I don’t have to google it every time I need a cheat sheet.

cPanel (WHM): Installing on a Clean Server

First off, a caveat: for installing any control panel it’s recommended to use a clean server. Otherwise the server may break after the panel is installed.

cPanel (WHM): Installing on a Clean Server

First off, a caveat: for installing any control panel it’s recommended to use a clean server. Otherwise the server may break after the panel is installed.

Using cPanel (WHM) to Manage a Cluster

WHM is a decent server management tool. It’s paid, but the developers did a solid job. It’s fairly common to install WHM/cPanel on a single server that holds...

Using cPanel (WHM) to Manage a Cluster

WHM is a decent server management tool. It’s paid, but the developers did a solid job. It’s fairly common to install WHM/cPanel on a single server that holds...

Adding meta tags to WordPress

By default WordPress doesn’t output the tags you set on a post anywhere in the page source. According to this article meta tag support was removed from WordP...

Adding meta tags to WordPress

By default WordPress doesn’t output the tags you set on a post anywhere in the page source. According to this article meta tag support was removed from WordP...

Setting Up a High Availability Cluster With Heartbeat on CentOS

In this note I want to cover using heartbeat with two servers as an example. In this example I have two servers running mysql. Sites connect to ip address 19...

Setting Up a High Availability Cluster With Heartbeat on CentOS

In this note I want to cover using heartbeat with two servers as an example. In this example I have two servers running mysql. Sites connect to ip address 19...

Setting Up a High Availability Cluster With Heartbeat on CentOS

In this note I want to cover using heartbeat with two servers as an example. In this example I have two servers running mysql. Sites connect to ip address 19...

Virtual users in Pure-Ftp

I would like to describe the way how to use virtual users in pure-ftpd.

WHM (cPanel): How to Kill a Stuck Transfer

Had to move accounts between servers today. Naturally used the WHM Transfer tool. One of the batches got stuck mid-process. Unfortunately the developers didn...

Mcrypt on WHM/cPanel

To enable mcrypt support in WHM you need to use the EasyApache module.

Mcrypt on WHM/cPanel

To enable mcrypt support in WHM you need to use the EasyApache module.

Mcrypt on WHM/cPanel

To enable mcrypt support in WHM you need to use the EasyApache module.

Backup webiste to Dropbox

The other day I was wondering about the correct backup of several WordPress sites and then uploading them to some free storage. I would like it to be done wi...

What LVM is and what it’s for

LVM - logical volume manager. It lets you combine several physical disks into one logical device and treat that as a single disk.

What LVM is and what it’s for

LVM - logical volume manager. It lets you combine several physical disks into one logical device and treat that as a single disk.

What LVM is and what it’s for

LVM - logical volume manager. It lets you combine several physical disks into one logical device and treat that as a single disk.

What LVM is and what it’s for

LVM - logical volume manager. It lets you combine several physical disks into one logical device and treat that as a single disk.

What LVM is and what it’s for

LVM - logical volume manager. It lets you combine several physical disks into one logical device and treat that as a single disk.

Installing Solr + Tomcat6 on CentOS

Solr doesn’t need tomcat to work. You can use its built-in functionality to run it on port 8983.

Installing Solr + Tomcat6 on CentOS

Solr doesn’t need tomcat to work. You can use its built-in functionality to run it on port 8983.

Enable Epel, Remi, Atrpms in RHEL/CentOS

It’s no secret that CentOS and other RedHat-like systems come with a standard set of repositories. Unfortunately, many required packages are missing.

Enable Epel, Remi, Atrpms in RHEL/CentOS

It’s no secret that CentOS and other RedHat-like systems come with a standard set of repositories. Unfortunately, many required packages are missing.

Enable Epel, Remi, Atrpms in RHEL/CentOS

It’s no secret that CentOS and other RedHat-like systems come with a standard set of repositories. Unfortunately, many required packages are missing.

Enable Epel, Remi, Atrpms in RHEL/CentOS

It’s no secret that CentOS and other RedHat-like systems come with a standard set of repositories. Unfortunately, many required packages are missing.

How to Connect to a Server over ssh from PHP

A small note on how to connect to a remote server from php, run a command and display the results on screen.

T-SQL Cheat Sheet - Part 1

In this post I put together a basic set of t-sql scripts that give you metadata about MSSQL. If you’ve ever tried getting some of this info through the GUI, ...

T-SQL Cheat Sheet - Part 1

In this post I put together a basic set of t-sql scripts that give you metadata about MSSQL. If you’ve ever tried getting some of this info through the GUI, ...

How to configure the log for HaProxy

To enable HaProxy logging edit /etc/sysconfig/rsyslog - bring the only line there to the following form:

The HaProxy statistics page

HaProxy provides a convenient tool for showing statistics in real time.

Converting Outlook PST to Thunderbird Format

If you decided to move from Windows to Linux and ran into the problem of importing mail from Outlook into Thunderbird, keep reading. The following script he...

Setting up replication with lsync

For replicating data between servers, NFS isn’t always the right tool. If you need the same content in two directories across several servers, lsync works we...

FFmpeg with libaacplus and fdk-aac support on CentOS

While working on a project for a client I needed to extend ffmpeg’s functionality and add a couple of features it doesn’t have out of the box. Needed to enab...

FFmpeg with libaacplus and fdk-aac support on CentOS

While working on a project for a client I needed to extend ffmpeg’s functionality and add a couple of features it doesn’t have out of the box. Needed to enab...

IpTables NAT in 3 steps

NAT — Network address translation — is a handy feature of any firewall, letting you translate the IP addresses of transit packets.

Perl Dancer + mysql + memcached

Most of the people writing Perl have heard about the Perl Dancer micro-framework. But did they use it for anything beyond generating a project, writing a ‘He...

How to add AdSense to WordPress - functions.php

Following up on the first post, here’s an alternative way to add AdSense to WordPress without plugins.

How to add AdSense to WordPress - functions.php

Following up on the first post, here’s an alternative way to add AdSense to WordPress without plugins.

Setting up a Linux server for WordPress/Drupal/Joomla

This is a practical guide to setting up a server for maximum performance running one of the blog-oriented CMS platforms: WordPress, Drupal, or Joomla.

Setting up a Linux server for WordPress/Drupal/Joomla

This is a practical guide to setting up a server for maximum performance running one of the blog-oriented CMS platforms: WordPress, Drupal, or Joomla.

Configuring ETags in IIS7

Entity tags (ETags) are the mechanism web servers and browsers use to determine whether an element in the browser cache matches the object on the server.

Configuring ETags in IIS7

Entity tags (ETags) are the mechanism web servers and browsers use to determine whether an element in the browser cache matches the object on the server.

SED Cheat Sheet

Sed is a stream editor on UNIX-like operating systems that is used to filter and transform text.

Index in MySQL tables

To create a unique index for a MySQL table, run this command:

How to Install Java JRE on Linux Ubuntu

This is about how to install the latest version of Java JRE on Linux Ubuntu.

How to Install Java JRE on Linux Ubuntu

This is about how to install the latest version of Java JRE on Linux Ubuntu.

Creating a child theme in WordPress

Inspired by an article on Habr, I decided to write my own take on creating a child theme in WordPress, since the Habr one has way too much text and explanati...

Doing match calculations in BASH with bc

bc is a tool that allows to do inline calculations in bash cli. Eventually bc can’t be used for complicated calculations.

Doing match calculations in BASH with bc

bc is a tool that allows to do inline calculations in bash cli. Eventually bc can’t be used for complicated calculations.

How to Get/Change the Plesk Admin Password from the Command Line

When you’re using the Plesk panel, admin and root are different users, and their passwords can differ. So you might have ssh access to the server as root and...

How to Get/Change the Plesk Admin Password from the Command Line

When you’re using the Plesk panel, admin and root are different users, and their passwords can differ. So you might have ssh access to the server as root and...

Simple and lightweight tabs with jQuery

A Habr user called Lzhedmitriy was not happy with the horizontal text tabs he found on the internet. As a result a simple jQuery plugin that does what he nee...

Meet Django

Django is a web framework written in Python, that provides a basic set of components for building a site. This article is about exactly that. I’ll cover sett...

Fixing MODX Revolution Errors on php v.5.4.13

While deploying MODX Revolution on a server with php v.5.4.13 I ran into a broken admin panel and search.

Installing the latest version of Python on Centos 6.5

The latest version of Python as of today is 3.4.2. To install the latest python version, first install the required packages:

Installing PostgreSQL 9.4 on Centos 6.5

A note on how to install PostgreSQL 9.4 on Centos 6.5.

Configure Apache for Python 3.4 on CentOS 6.5

To install the latest version of Python 3.4 on CentOS 6.5, you can use the previous article.

Enabling geodata support in Apache, or building mod_geoip from source

While working on a WHM server I ran into the following problem installing mod_geoip:

Enabling geodata support in Apache, or building mod_geoip from source

While working on a WHM server I ran into the following problem installing mod_geoip:

Restoring the root user’s password in Linux

Stuff happens in life, and root passwords get lost. So what do you do when you need into the system and the password is gone? The actual question: how do you...

Working with fault-tolerant NFS servers

FireWall in CentOS7

In CentOS7 you can no longer edit the usual iptables firewall rules the way you’re used to. iptables itself is still there, but it’s now wrapped in firewalld...

Using expect in bash scripts

Expect is a wrapper that provides the ability to program the input for interactive programs. Interactive programs are applications that require the input of ...

Thoughts on Clustering: Part 4 - Need More WEB

After a long quiet spell I decided to continue the story about branching out the server lineup. That phrase came out vague. It’ll make sense as we go.

Mysqldump using PHP

I’ve run into this more than once: you need to pull a dump of a large database from hosting, but there’s no remote access to the mysql engine. PhpMyAdmin mig...

Run Yii in Docker container locally

In this article I want to tell you what I did to automatically deploy NginX, php-fcgi and install Yii using docker. It can be usefull for local development. ...

Importing posts from WordPress into Yii

Riding the wave of the previous post, I decided to play around with Yii and try porting this site, posts and pages included, over to Yii.

NginX and X-Forwarded-Proto:HTTPS behind a load balancer

A quick note about https traffic behind crooked load balancers. We have Setting up Nginx + php-fcgi behind a load balancer. A load balancer is like a woman -...

Creating an administrator Account in OpenX from MySQL

Creating an admin from the admin panel isn’t a hard task. But what do you do if you don’t have access to the admin panel, but you do have access to the mysql...

Use mod_substitute in Apache

The essence mod_substitute is to replace the text in the body of the response from the web server. With it you can change for example links to one domain wit...

Server Not Showing Up in NewRelic

This isn’t an article, just a note for the blog of an ordinary tech guy.

Installing monit on Debian/Ubuntu

Monit — a program for checking the state of services and keeping them running, which can send notifications when something goes wrong. It runs on linux, bsd ...

Installing monit on Debian/Ubuntu

Monit — a program for checking the state of services and keeping them running, which can send notifications when something goes wrong. It runs on linux, bsd ...

Configure SFTP Chroot at Ubuntu 14.04

This article covers setting up an sftp server and isolating users in their home directories (chroot) based on Linux Ubuntu 14.04.

Configure suexec for Apache2 on Ubuntu 14.04

The suexec mechanism allows you to execute CGI scripts on behalf of different system users. In this article, I’ll walk through an example of setting up suexe...

Configure suexec for Apache2 on Ubuntu 14.04

The suexec mechanism allows you to execute CGI scripts on behalf of different system users. In this article, I’ll walk through an example of setting up suexe...

Configure suexec for Apache2 on Ubuntu 14.04

The suexec mechanism allows you to execute CGI scripts on behalf of different system users. In this article, I’ll walk through an example of setting up suexe...

Configure suexec for Apache2 on Ubuntu 14.04

The suexec mechanism allows you to execute CGI scripts on behalf of different system users. In this article, I’ll walk through an example of setting up suexe...

Migrating a Site Away from GoogleSites

Today habrahabr user ‘lord Brabazon Vere-de-Vere’ shared his method for migrating a site off GoogleSites onto separate hosting.

Migrating a Site Away from GoogleSites

Today habrahabr user ‘lord Brabazon Vere-de-Vere’ shared his method for migrating a site off GoogleSites onto separate hosting.

Netstat not found on Fedora

Today, while doing initial setup on a Fedora 20 server, I got this error:

Netstat not found on Fedora

Today, while doing initial setup on a Fedora 20 server, I got this error:

Disk space issue in Linux

Sometimes there’s plenty of free space on disk, but files stubbornly refuse to get created. In some cases you get an error saying the disk ran out of free sp...

Disk space issue in Linux

Sometimes there’s plenty of free space on disk, but files stubbornly refuse to get created. In some cases you get an error saying the disk ran out of free sp...

RackSpace Cloud API - getting the token and the endpoint

RackSpace is an American hosting provider with several data centers, offering a big number of hosting solutions. One of the products is cloud hosting with it...

Puppet - Entry Point

Puppet is a set of utilities written in Ruby that let you manage a large number of servers from one place. It lets you describe the desired state for every s...

Full Upgrade: NginX 1.9 + PHP7 + MySQL 5.6 on Ubuntu 14.04

Summer’s winding down and my hosting year with amazon is starting over. Decided to spin up a new server with everything on the latest versions.

Full Upgrade: NginX 1.9 + PHP7 + MySQL 5.6 on Ubuntu 14.04

Summer’s winding down and my hosting year with amazon is starting over. Decided to spin up a new server with everything on the latest versions.

Full Upgrade: NginX 1.9 + PHP7 + MySQL 5.6 on Ubuntu 14.04

Summer’s winding down and my hosting year with amazon is starting over. Decided to spin up a new server with everything on the latest versions.

Mail Gets Delivered Through the plesk_virtual Service

By default, when you create an account in Plesk, local mail delivery gets enabled for it. No matter how many times you tell it to route mail according to the...

Configuring Postfix to send mail through MailGun

This article is about how to configure your Linux server to send mail through the MailGun service.

Moving a blog between WordPress multisite installations

There are plenty of articles online describing how to move a blog out of multisite into a standalone WordPress.

Moving a blog between WordPress multisite installations

There are plenty of articles online describing how to move a blog out of multisite into a standalone WordPress.

Error: xz compression not available

If you get the following message while trying to install any package with yum, it means you picked the wrong repo package during install:

Displaying ServerVariables in IIS

A lot of admins use the phpinfo function to debug the headers the server gets when the site is requested.

Making a backup of all the databases in MSSQL 2008/2012

To make backup copies of all the databases on your MSSQL 2008/2012 server you can use the following SQL query:

Using WebDeploy to move IIS sites between servers

Using WebDeploy makes the task of moving the configs and the content of the sites between Windows servers much easier. WebDeploy is irreplaceable when you wo...

Using WebDeploy to move IIS sites between servers

Using WebDeploy makes the task of moving the configs and the content of the sites between Windows servers much easier. WebDeploy is irreplaceable when you wo...

Using Loops in the Windows Command Line

After years working in the linux console, it’s really hard to do tasks on windows servers.

Using Loops in the Windows Command Line

After years working in the linux console, it’s really hard to do tasks on windows servers.

Using Loops in the Windows Command Line

After years working in the linux console, it’s really hard to do tasks on windows servers.

Upgrading Apache 2.2.31 OpenSSL 1.0.1q on CentOS 6.7

In recent times, I’ve increasingly encountered the need to update OpenSSL to its latest version on servers. Unfortunately, so much relies on the OpenSSL libr...

Disable Diffie-Hellman Modulus vsFTPD

I couldn’t find how to disable Diffie-Hellman encryption in vsFTPD TLS.

Securing Weak Points in Apache SSL Configuration

Vulnerabilities are occasionally found in the SSL protocol, which enables encrypted traffic exchange between a server and a client. These vulnerabilities pot...

Securing Weak Points in Apache SSL Configuration

Vulnerabilities are occasionally found in the SSL protocol, which enables encrypted traffic exchange between a server and a client. These vulnerabilities pot...

Securing Weak Points in Apache SSL Configuration

Vulnerabilities are occasionally found in the SSL protocol, which enables encrypted traffic exchange between a server and a client. These vulnerabilities pot...

Securing Weak Points in Apache SSL Configuration

Vulnerabilities are occasionally found in the SSL protocol, which enables encrypted traffic exchange between a server and a client. These vulnerabilities pot...

Working with the mail queue in Qmail

Qmail is not the last word in mail delivery technology, but this smtp daemon is still very widespread. In particular many servers with the Plesk panel use ex...

Quickly building an rpm package in CentOS with Checkinstall

To build an RPM package from an application’s source code you need Checkinstall.

Building NginX v.1.9.10 from source

Installing any software by compiling the package from source is the best way to get the latest versions.

Adding sites to IIS7 from the command line

A quick note on how to create a site in IIS7 from the command line (cmd.exe). It is very handy if you need to create 100+ sites.

Adding sites to IIS7 from the command line

A quick note on how to create a site in IIS7 from the command line (cmd.exe). It is very handy if you need to create 100+ sites.

Adding sites to IIS7 from the command line

A quick note on how to create a site in IIS7 from the command line (cmd.exe). It is very handy if you need to create 100+ sites.

Setting up Nginx + perl-fcgi

Everyone praises Nginx for its performance. But nobody accounts for the fact that it’s so fast because it’s missing all those modules that extend Apache’s fu...

Scan server with Lynis

Lynis (formerly RkHunter) is a security auditing tool for Linux and BSD systems. It performs a detailed audit of many aspects of your system’s security and c...

Scan server with Lynis

Lynis (formerly RkHunter) is a security auditing tool for Linux and BSD systems. It performs a detailed audit of many aspects of your system’s security and c...

Scan Linux server with maldetect

Malware Detect (LMD) is a utility that scans Linux systems for malicious files (malware). Distributed under the GNU GPLv2 license.

Scan Linux server with maldetect

Malware Detect (LMD) is a utility that scans Linux systems for malicious files (malware). Distributed under the GNU GPLv2 license.

Use DKIM signature for outgoing emails

Email spoofing is the creation of email messages with a forged sender address. There are many services that provide protection from spoofing.

Use DKIM signature for outgoing emails

Email spoofing is the creation of email messages with a forged sender address. There are many services that provide protection from spoofing.

How to configure Exim to use SendGrid to send mail

I continue my series of articles about email services until the inspiration from the recently solved problems wears off.

How to configure Exim to use SendGrid to send mail

I continue my series of articles about email services until the inspiration from the recently solved problems wears off.

Installing NewRelic Plugins with NPI: MySQL Example

Most people know newrelic.com - a service for tracking application state and performance. This service is developing pretty fast and the developers keep expa...

Installing NewRelic Plugins with NPI: MySQL Example

Most people know newrelic.com - a service for tracking application state and performance. This service is developing pretty fast and the developers keep expa...

Configure SELinux for Apache on CentOS

SELinux is a Linux kernel module that provides an additional mechanism to determine folder and file permissions. Sometimes it creates considerable problems w...

OSSEC client-server installation

OSSEC is an open source attack detection and prevention system. It can be configured to monitor not only events in log files but also changes to files and ru...

Amazon CloudFront and the Access-Control-Allow-Origin error

The other day we deployed a Magento shop in the Amazon cloud. Everything would be fine, but the browser console keeps showing the following error:

Setup Unison in CentOS 7

Unison is one of the utilities that is used to replicate files between servers. A big advantage of Unison is its support for master-master replication.

Setup Unison in CentOS 7

Unison is one of the utilities that is used to replicate files between servers. A big advantage of Unison is its support for master-master replication.

Change default umask for files in custom folder

Umask in Linux is a pattern of permissions for created files. Typically specified globally in /etc/profile or on a per-user basis in .bashrc files in the hom...

Change default umask for files in custom folder

Umask in Linux is a pattern of permissions for created files. Typically specified globally in /etc/profile or on a per-user basis in .bashrc files in the hom...

Change default umask for files in custom folder

Umask in Linux is a pattern of permissions for created files. Typically specified globally in /etc/profile or on a per-user basis in .bashrc files in the hom...

Vagrant authorization issue when executing kitchen create in Chef

Chef can fail with the following error running kitchen create command if you have Vagrant 1.8.5:

Vagrant authorization issue when executing kitchen create in Chef

Chef can fail with the following error running kitchen create command if you have Vagrant 1.8.5:

Configure RabbitMQ failover cluster

RabbitMQ is a universal bus to be used to exchange messages between the applications. There are other solutions like Kafka, AWS SQS, Google Pubsub, etc. If y...

Get Inique IP addresses from Apache access.log

The following can be used to fetch the unique records from apache access.log. This example covers IP addresses of the clients but this example can be used to...

Install Nginx from the source code

There are many casess when we need to compile the the sofware from the source code. Nginx is a briliant case when the can’t enable geoip module or mod_securi...

Jenkins auth over AWS Cognito

Jenkins auth over AWS Cognito

DevOps CoE Best practices

DevOps Center of Exelence (CoE) is a new trend in team work when DevOps team is no longer concentrated on the single project. It is more a service team insid...

More examples with terraform for and for_each loops

Loops in terraform is not something new. There is a bunch of articles with examples in the internet. However I had a number of cases when I could not find th...

Cloudflare: restrict access to your website for a country

Today I woke up and suddenly realised that most of the articles in this blog were written in russian language and the major visitors come from russian-speeki...

Find neighbors of the matrix element at the given position

I force myself to learn something but before learning something new I need to memorize what I knew before. So I take python labs at exercism.org.

Start and Stop Ec2 Instances with CloudWatch Event rule and Lambda

This note can be usefull for those of you who needs to hav EC2 instance running during the certain period of time during the day and awoid spending money whe...

Start and Stop Ec2 Instances with CloudWatch Event rule and Lambda

This note can be usefull for those of you who needs to hav EC2 instance running during the certain period of time during the day and awoid spending money whe...

Use gitlab to store terraform state file

This is a short note about the way to configure your GitlabCI to store the Terraform state file. Terraform backend configuration remains pretty simple: terra...

List items should be accessed using square brackets

This is a note about the following error that is produced by tflint Warning: List items should be accessed using square brackets (terraform_deprecated_index)...

GIT cheatsheet

This is one of the cheetsheets I have at this website. The primary purpose of this one is to collect all usefull commands you might need in your daily work. ...

Using git-crypt to encrypt sensitive data in your git repository

This is another note of the kind: “I don’t want to google for it next time I need it in few years”

GCP organization and folder structure for a startup after Series A

Recently I had a case where a startup closed their Series A and was still running everything out of one GCP project tied to the founder’s personal Google acc...

AWS account structure for a startup after Series A

Same story as the GCP version of this note, different cloud: startup closes Series A, and the AWS side is still one root user, one account, prod and the sand...

psql command line cheat sheet

I switch between MySQL and PostgreSQL often enough that the psql meta-commands never stick in my head. Every time it’s the same five minutes of googling \d v...