Published on

This article introduces LAMP software stack on zLinux (Linux on IBM System z). Let’s call it zLAMP. We will delve into configuring and starting up individual components of zLAMP and then downloading, installing and testing few LAMP based off the shelf open source applications

Published in: Technology
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide


  1. 1. zLAMPIntroductionIn recent years, web development and deployment has become extremely fast and easy with the usage of opensource software development tools and frameworks. The usage of open source software has reduced capital andoperating expenses for web startups to a greater extend that there is a significant increase in the volume of newinternet startups with applications developed using open source software.One of the widely used open source stack for web application development is LAMP. As the expansion implies,LAMP stack consists of a web server (Apache), a database server (MySQL) and a set of scripting languages(PHP/Perl/Python) that can run on any flavor of Linux. In general it is described as an open source operating system,open source web server, open source database server and open source programming languages. The Linux,Apache, MySQL, PHP (LAMP) stack can provide an efficient and cost effective open source architecture to build andrun web applications.This article introduces LAMP software stack on zLinux (Linux on IBM System z). Let’s call it zLAMP. We will delveinto configuring and starting up individual components of zLAMP and then downloading, installing and testing fewLAMP based off the shelf open source applications.Why zLAMP StackLinux on System z combines the advantages of the IBM mainframes with the flexibility and open standards of theLinux operating systems. System z’s high virtualization and utilization capabilities make it an ideal platform forrunning LAMP based web applications than x86 servers. Linux on System z virtual servers are enabled by default forvertical scalability, thus making it possible to meet scalability requirements by enhancing with additional processors ormemory dynamically. If the vertical scalability is not sufficient, a new Linux image on system z can be deployed withinminutes without interrupting the operations.Recently, LAMP based social network Facebook has migrated some of their application modules to non LAMP stackdue to high scaling demands which often caused outages of their x86 servers. Even though LAMP on x86 systems ishighly reliable and cost effective alternative compared to other web development stacks, it can meet extremescalability requirements if it runs on top of a hardware (like System z) with high resource (Processor, Memory,Storage, Networks etc) virtualization capabilities.In x86 world, different LAMP components might be running on dedicated Linux servers. All these servers can beconsolidated to run on one physical System z machine. This saves power and space in the datacenter, and reducesthe administration efforts while meeting scalability needs very efficiently.zLAMP ComponentsThe zLAMP acronym points more to a selection of one the "P" elements (PHP, Perl, and Python) rather than to aneed for the inclusion of all of them. It’s more likely to find both Perl and Python useful tools for administrative tasks,so theyll probably be installed on system whether or not your intent is to use them as an element of LAMP webdevelopment. Enterprise Linux distributions for System z provide the most recent version of each of these packagesavailable along with the Enterprise Linux version release. Apache, PHP, Perl, and Python are provided as defaults inthe installation of Enterprise Linux, while MySQL requires selection at the time of installation.zLinux: Clearly, the most important element of the zLAMP combination is the Linux distribution installedon System z server. With dozens of System z specific distributions available, the choice can be a bitperplexing. Of the available distributions, however, Enterprise Linux (RedHat or SuSe) has grabbed thestrongest niche in enterprise-grade LAMP web servers for several reasons.
  2. 2. Apache Server: Apache web server has been dominant web server since 1996 and has since evolved torival other web servers in terms of functionality and performance. In 2009 it became the first web serversoftware to surpass the 100 million web site milestone. Apache is primarily used to serve both staticcontent and dynamic Web pages on the World Wide Web.MySQL Database: MySQL is a multithreaded, multi-user, SQL database management system (DBMS)MySQL database has grown the world’s most popular open source database with over eleven millioninstallations worldwide. Free-software projects that require a full-featured database management systemoften use MySQL.PHP/Perl/Python: These are reflective programming language originally designed for producing dynamicweb pages. They are often used to create powerful and yet intuitive web based applications that accessbackend systems, content management systems or databases.The scripting component of zLAMP varies depending on different installations. Most commonly, PHP isused in conjunction with the other components. However, Perl or Python are also viable options. Thesegeneral scripting languages can be modified in open source and embedded with standard HTML code toexecute dynamic or "on-the-fly" website content based on specific actions taken by the user.With these components, zLAMP offers a full service web development platform through open source thatallows website programmers and designers to create sites rich in customized content.ConfigurationOpen source tools have some great advantages over other proprietary tools. Among those advantages isthe general ability to configure the tools by editing a text-based configuration file. Nearly any setting canbe configured and modified by editing these files. That allows the user to create a configuration thatscustomized for the particular and unique use of the tool, down to the smallest detail.As zLAMP components are installed by default along with the OS installation, this section will focus onconfiguration of each components. If any of the components are not available (check version commandsto confirm availability) as part of the installation, follow the same installation instructions for x86 Linuxdistributions.Configuring Apache:The text configuration file for the Apache server in Enterprise Linux is located at /etc/httpd/conf/httpd.conf.While the file offers complete customization of all the server parameters, to run apache web server firstmake a small modification to the apache configuration file, then start the Apache service (known as“httpd”), and finally configure it so it will always start when the machine is booted: cd /etc/httpd/conf cp httpd.conf httpd.conf.orig vi httpd.confFind the line with #ServerName new.host.name:80 and add below it: ServerName zlinuxsvNext, let us start the web server, and configure it so that it will automatically start on the next reboot. Typethe following into the shell window: service httpd start
  3. 3. chkconfig httpd onTo test Apache, bring up a web browser with URL http://localhost or with the IP Address of the zLinuxserver. You should see apache test web page indicating that the Apache HTTP server is runningproperly.Configuring MySQL:Before starting MySQL, you’ll need to create a MySQL configuration file from one of the standard onesoffered. MySQL delivers several example configuration files in its packages. At least four differentvariations of the server configuration are available. As root, copy the standard small configuration file to/etc/my.cnf and add 4 lines to the end of it.Type the following into the terminal window: cd /etc cp /usr/share/doc/mysql/my-small.cnf my.cnfNext you need to start the MySQL service (called “mysqld”), and set it to always start when the machinestarts. Type the following into the terminal shell: service mysqld start chkconfig mysqld onNow configure user access to the MySQL database. To change root’s password (replace the final“password” with your root password), give privileges to the web user, and remove the default anonymoususer, type the following into the terminal shell: mysqladmin -u root password password mysql -pThis will prompt you for the password you just entered above, and start the MySQL monitor. You will needto ensure that you also add access based on your specific host name as well (i.e.web@localhost.localdomain). Type the following at the mysql> prompt: grant all privileges on *.* to web@localhost identified by web; grant all privileges on *.* to web@zlinuxsv identified by web; delete from mysql.user where User=; exitLogin as web and test out MySQL: su – web mysql –u web ––password=webThis will start the MySQL monitor as the user “web”. Type the following at the mysql> prompt to test it: show databases;You should get output that looks something like:
  4. 4. +----------+ | Database | +----------+ | mysql | | test | +----------+ 2 rows in set (0.00 sec)This shows that MySQL has been installed with the initial two databases. MySQL administration taskscan be performed from a web based interface using phpMyAdmin open source application.Configuring PHP:As root, edit the PHP configuration file to point to the correct host and allow access to the web user, thenrestart Apache to read changes. Following are the commands to be issued at the terminal: cd /etc cp php.ini php.ini.orig vi php.iniChange three lines to read as follows: mysql.default_host = zlinuxsv mysql.default_user = web mysql.default_pw = webSave the document, then continue typing the following into the terminal shell window to restart the webserver and put the changes just made into effect: service httpd restartTo test PHP, create a test PHP page. Type the following into the terminal window: cd /var/www/html vi default.phpAdd the following to the file: <html> <head> <title>PHP Test Page</title> </head> <body> <?php echo “<hr />”; echo “<p align=center>This is a test of PHP!</p>”; echo “<hr />”; ?> </body> </html>To test, use your browser to access http://localhost/default.php
  5. 5. Out of the Box ApplicationsNow we are ready to test zLAMP stack by installing and configuring LAMP based applications on zLinux.This section of the article describes setting up of three off the shelf open source applications a) Wiki b)Blog and c) Content Management System (CMS) on zLinux (Fig.1). Fig. 1 Out of the box applications on zLinuxWordPressPopular open source blog hosting platform WordPress can be setup on zLinux by downloading the sourcefrom wordpress.org website. Unzip the downloaded tar file into a folder which the apache server canaccess. Typically, root html document folder (/var/www/html) is used for installation.Configuration of WordPress includes the setup of a database and the modification of the WordPressconfiguration file. WordPress uses a MySQL database to store the data. Therefore a database withspecific user privileges must be setup. root@msat$ mysql -u root -p mysql> CREATE DATABASE wordpressdb; mysql> GRANT ALL PRIVILEGES ON wordpressdb.* TO "wordpress"@"localhost" IDENTIFIED BY "<password>"; mysql> FLUSH PRIVILEGES; mysql> quitIn the example, the “root” user is the MySQL admin who creates the database “wordpressdb” and grantsthe privileges to the new user “wordpress”.Next step is to copy the sample configuration file /var/www/html/wordpress/wp-configsample.php to theconfiguration file which gets recognized by WordPress modules, which is /var/www/html/wordpress/wp-config.php. Adopt the settings for the MySQL database into the configuration file/var/www/html/wordpress/wp-config.php as user “root” with following attributes: define(DB_NAME, wordpressdb); define(DB_USER, web); define(DB_PASSWORD, web); define(DB_HOST, localhost);
  6. 6. Now, restart the Apache HTTP server and access WordPress from the URL http://localhost/wordpressMediaWikiMediaWiki, the project behind Wikipedia, is a Wiki implemented in PHP. Download mediawiki packagesfrom the MediaWiki webpage and unzip all files into a folder which the Apache Web server can access.Toconfigure MediaWiki start a Web browser and open the URL http://localhost/mediawiki/config. Follow theinstructions on the web page and complete the configuration by clicking “Install MediaWiki!”.It is important to place the configuration file localsettings.php, which has been created during theconfiguration step, into the MediaWiki main folder. This can be opted during the configuration from theinstallation web page of MediaWiki or can be manually moved by issuing following command at terminal: root@msat$ mv /var/www/html/mediawiki/config/LocalSettings.php /var/www/html/mediawikiFinally, restart the Apache HTTP server and access MediaWiki at http://localhost/mediawiki.DrupalA Content Management System (CMS) is used to organize content of different types such as documents,multimedia files, Web pages or other electronic data. Drupal is a highly popular content managementsystem (CMS) implemented in PHP. Like other packages explained earlier, Drupal package also need tobe extracted into a folder where Apache have read and write access.The configuration of Drupal includes the setup of a database and the execution of the installation wizard.Drupal can use a MySQL database to store the information. Drupal setup with specific MySQL databaseuser privileges is achieved using following commands: root@msat$ mysql -u root -p mysql> CREATE DATABASE drupaldb; mysql> GRANT ALL PRIVILEGES ON drupaldb.* TO "drupal"@"localhost" IDENTIFIED BY "<password>"; mysql> FLUSH PRIVILEGES; mysql> quitNow, start the Drupal installation wizard, open a Web browser and access the wizard at the following theURL http://localhost/drupal. The upcoming wizard guides the user to complete the setup. After the wizardcompleted, change the access rights of the Drupal configuration file settings.php. root@msat$ chmod a-w /var/www/html/drupal/sites/default/settings.phpOnce installation is complete, restart the Apache HTTP server and access Drupal athttp://localhost/drupalConclusionSystem z’s powerful virtualization capabilities make it possible to run multiple Linux images inside a singleSystem z box. Scalability needs of web applications can be easily met by bringing up additional Linuximages as clones of existing images without interrupting services to end users. Moreover, presence of
  7. 7. System z architecture ensures high utilization rates for all the underlying components of a webapplication.Combining the features of open source software and System z, zLAMP based web applications can beextremely reliable, highly available and zero fault tolerant systems compared to x86 based systems. Sowhen building your next web application, remember to consider using LAMP on system z. If you alreadyhave one at the center of your mission-critical enterprise, you already know the advantages of usingSystem z for hosting large scale web applications.References1 Web 2.0 with RHEL 5 http://goo.gl/PHxtG2 WordPress project http://wordpress.org3 MediaWiki project http://mediawiki.org4 Drupal project http://drupal.org/5 phpMyAdmin project http://www.phpmyadmin.net/6 Linux on System z Distributions http://goo.gl/9jvf1