™ SPONSORED BY Since 1994: The Original Magazine of the Linux Community AUGUST 2014 | ISSUE 244 | www.linuxjournal.com PROGRAMMING HOW-TO: + OpenGL Build, Develop Programming and Validate Creation of RPMs USE VAGRANT Sysadmin Cloud for an Easier Troubleshooting Development with dhclient Workflow Tips for PROMISE Becoming a THEORY Web Developer An In-Depth A Rundown Look of Linux for Recreation V WATCH: ISSUE OVERVIEW LJ244-Aug2014.indd 1 7/23/14 6:56 PM Get the automation platform that makes it easy to: Build Infrastructure Deploy Applications Manage In your data center or in the cloud. getchef.com LJ244-Aug2014.indd 2 7/23/14 11:41 AM Are you tiredtiered of of dealing dealing with with proprietary proprietary storage? storage? ® 9%2Ä4MHÆDCÄ2SNQ@FD ZFS Unified Storage zStax StorCore from Silicon - From modest data storage needs to a multi-tiered production storage environment, zStax StorCore zStax StorCore 64 zStax StorCore 104 The zStax StorCore 64 utilizes the latest in The zStax StorCore 104 is the flagship of the dual-processor Intel® Xeon® platforms and fast zStax product line. With its highly available SAS SSDs for caching. The zStax StorCore 64 configurations and scalable architecture, the platform is perfect for: zStax StorCore 104 platform is ideal for: VPDOOPHGLXPRIILFHILOHVHUYHUV EDFNHQGVWRUDJHIRUYLUWXDOL]HGHQYLURQPHQWV VWUHDPLQJYLGHRKRVWV PLVVLRQFULWLFDOGDWDEDVHDSSOLFDWLRQV VPDOOGDWDDUFKLYHV DOZD\VDYDLODEOHDFWLYHDUFKLYHV TalkTalk with with an anexpert expert today: today: 866-352-1173 866-352-1173 - http://www.siliconmechanics.com/zstax LJ244-Aug2014.indd 3 7/23/14 11:41 AM AUGUST 2014 CONTENTS ISSUE 244 PROGRAMMING FEATURES 64 Vagrant 74 An Introduction to How to use Vagrant to create a OpenGL Programming much easier development workflow. Is it difficult to rotate a 3-D cube Richard Delaney in OpenGL? Mihalis Tsoukalos ON THE COVER /V^;V!6WLU.37YVNYHTTPUNW <ZL=HNYHU[MVYHU,HZPLY+L]LSVWTLU[>VYRMSV^W 7YVTPZL;OLVY`HU0U+LW[O3VVRW )\PSK+L]LSVWHUK=HSPKH[L*YLH[PVUVM974ZW :`ZHKTPU*SV\K;YV\ISLZOVV[PUN^P[OKOJSPLU[W ;PWZMVY)LJVTPUNH>LI+L]LSVWLYW (9\UKV^UVM3PU\_MVY9LJYLH[PVUW Cover Image: © Can Stock Photo Inc. / Krisdog 4 / AUGUST 2014 / WWW.LINUXJOURNAL.COM LJ244-Aug2014.indd 4 7/23/14 11:41 AM INDEPTH 90 Promise Theory—What Is It? Promise Theory has been adopted more widely in recent years in connection with Software Defined Networking as it embodies many of the principles on which networking is based. Mark Burgess 22 96 Integrating Trac, Jenkins and Cobbler—Customizing Linux Operating Systems for Organizational Needs A process to build, develop and validate creation of RPMs to be included with the Scientific Linux distribution deployed on HPC systems. David Brown COLUMNS 48 30 Reuven M. Lerner’s At the Forge First Steps with Web Development 38 Dave Taylor’s Work the Shell Days Between Dates: the Counting 74 44 Kyle Rankin’s Hack and / Not So Dynamic Updates IN EVERY ISSUE 48 Shawn Powers’ The Open-Source Classroom 8 Current_Issue.tar.gz First Health, Now Recreation 10 Letters 16 UPFRONT 108 Doc Searls’ EOF 28 Editors’ Choice Can We Stop Playing Card Games 60 New Products with Business? 111 Advertisers Index LINUX JOURNAL (ISSN 1075-3583) is published monthly by Belltown Media, Inc., 2121 Sage Road, Ste. 395, Houston, TX 77056 USA. Subscription rate is $29.50/year. Subscriptions start with the next issue. WWW.LINUXJOURNAL.COM / AUGUST 2014 / 5 LJ244-Aug2014.indd 5 7/23/14 11:41 AM Executive Editor Jill Franklin [email protected] Senior Editor Doc Searls [email protected] Associate Editor Shawn Powers [email protected] Art Director Garrick Antikajian [email protected] Products Editor James Gray [email protected] Editor Emeritus Don Marti [email protected] Technical Editor Michael Baxter [email protected] Senior Columnist Reuven Lerner [email protected] Security Editor Mick Bauer [email protected] Hack Editor Kyle Rankin lj@greenfly.net Virtual Editor Bill Childers [email protected] Contributing Editors )BRAHIM (ADDAD s 2OBERT ,OVE s :ACK "ROWN s $AVE 0HILLIPS s -ARCO &IORETTI s ,UDOVIC -ARCOTTE 0AUL "ARRY s 0AUL -C+ENNEY s $AVE 4AYLOR s $IRK %LMENDORF s *USTIN 2YAN s !DAM -ONSEN Publisher Carlie Fairchild [email protected] Director of Sales John Grogan [email protected] Associate Publisher Mark Irgang [email protected] Webmistress Katherine Druckman [email protected] Accountant Candy Beauchamp [email protected] Linux Journal is published by, and is a registered trade name of, Belltown Media, Inc. 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LJ244-Aug2014.indd 6 7/23/14 11:41 AM '14HPCadLinuxJnl.qxp_Layout 1 6/17/14 10:21 AM Page 1 SAVE 11th Annual THE DATE 2014 HIGH PERFORMANCE COMPUTING FOR WALL STREET Show and Conference (Monday) September 22, 2014 RooseveltMadison Ave and 45th Hotel, St, next to Grand NYC Central Station Big Data, Cloud, Linux, Low Latency, Networks, Data Centers, Cost Savings. Wall Street IT professionals and programmers will assemble at this 2014 HPC Show and Conference, Sept. 22. New for 2014 – Database Month programmers to speak on the program. his 11th Annual HPC networking opportunity will assemble 600 Wall Street TIT professionals at one time and one place in New York on September 22. This HPC for Wall Street conference is focused on High Put-through, Low Latency, Networks, Data Centers, lowering costs of operation. Our Show is an efficient one-day showcase and networking opportunity. Leading companies will be showing their newest systems live on-the-show floor. Register in advance for the full conference program which includes general sessions, drill-down sessions, an industry luncheon, coffee breaks, exclusive viewing times in the exhibits, and more. Save $100. $295 in advance. $395 on site. Don’t have time for the full Conference? Attend the free Show. Register in advance at: www.flaggmgmt.com/hpc Wall Street programmers will lead Show Hours: Mon, Sept 22 8:00 - 4:00 drill-down sessions in the Grand Conference Hours: 8:30 - 4:50 Ballroom program. September 2013 Sponsors Media Sponsors ™ Show & Conference: Flagg Management Inc 353 Lexington Avenue, New York 10016 (212) 286 0333 fax: (212) 286 0086 [email protected] Visit: www.flaggmgmt.com/hpc LJ244-Aug2014.indd 7 7/23/14 11:41 AM Current_Issue.tar.gz Chocolate in SHAWN POWERS My Peanut Butter rogramming always has been that If that sounds silly, that’s because it is! “thing” people did that I never Shell scripting is programming, and if Punderstood. You’ve heard me you’ve ever created sysadmin scripts or lament about my lack of programming even written batch files in Windows, skills through the years, and honestly, your programming skills are better I never thought I’d need to learn. Then than you think. along came the DevOps mentality, and I Kyle Rankin addresses an issue this started introducing programmatic ways month that can be really frustrating if of managing my system administration you’re automating a cloud environment. world. And you know what? If you spin up a server that gets Programming is pretty awesome. assigned a random IP address, how do Reuven M. Lerner starts off the you address it from the rest of your programming issue with a great article on infrastructure? He shows us his method how to begin in the Web development of dealing with that scenario and field. If you’re like me, and have been teaches us about DHCP along the way. ushered into the programmer’s world I decided to continue our summer blindfolded and scared, Reuven has a vacation a bit with my Open-Source great starting point for you. Dave Taylor Classroom column and talk about also teaches us programming as he recreation. Last month, I covered continues his lessons on scripting dates health-related technology, and so and counting days. For some reason, shell this month, I’m discussing mental- scripting doesn’t seem like programming, health-related technology—namely, and I’m far more comfortable doing it. games, TV, books and music. Next month, will be all command line and V VIDEO: learning, but here I focus on enjoying Shawn Powers runs the technology that is supposed to through the latest issue. make our lives so much easier! 8 / AUGUST 2014 / WWW.LINUXJOURNAL.COM LJ244-Aug2014.indd 8 7/23/14 11:41 AM CURRENT_ISSUE.TAR.GZ Next up is Richard Delaney. If you’ve one-size-fits-all solution to technology ever tried to automate your infrastructure needs. For many use cases, that’s still with something like Chef or Puppet, you true. If your organization needs a custom know that spinning up VMs on demand Linux distribution or needs to develop can be challenging. With Vagrant, something slightly different from what a creating a brand-new virtual machine is mainstream distro offers, that flexibility a simple one-liner. It supports multiple proves to be malleable as well. David virtualization platforms, multiple host Brown walks through customizing a Linux OSes and abstracts the underlying operating system to fit specific needs, process. Richard walks through using including custom development and system Vagrant in your VM infrastructure.