The greatest open source software of all time
InfoWorld's Open Source Hall of Fame recognizes the 36 most important free open source software projects in history (and today)Follow @infoworld
Full compiled programming languages aren't for everyone, and several popular open source scripting languages are remaking the application development landscape. These include Perl, Python, PHP, and Ruby, all of which can be used to help with systems administration tasks or create rich Internet applications. A salute to Sun is also in order, for releasing its Java language and JIT compiler under the GPL, bringing them into the open source community.
To make full use of scripting languages, it is often necessary to bring a database along for the ride -- and open source has you covered. The open source community has two 800-pound gorillas in the database category: MySQL and PostgreSQL. Both of these are strong database servers that can handle heavy loads, supporting clustering and including a wide range of enterprise-level features. And let's not forget a database scripter's best friends, phpMyAdmin and phpPgAdmin. These Web-based front ends (for MySQL and Postgres, respectively) make it easy for a programmer or DBA to easily set up a database and table structure, run queries, and of course add, delete, or manipulate the data.
Perhaps the most venerable of our revered hall of famers is the BIND (Berkeley Internet Name Domain) domain name server, which dates from the pioneer days of the Internet. The Internet runs on DNS, and DNS runs on BIND. There is probably no more important technology to enable the many various Internet applications that we all enjoy today. From Web pages to Internet VoIP telephony to the new social media applications such as Twitter and Facebook, almost everything we do on the Internet depends on DNS. The last numbers we've seen on the subject estimate that approximately 85 percent of DNS servers are running BIND.
The most pervasive form of communication on the Internet is still e-mail. Thus we must pay homage to three of the most widely used open source mail servers: Sendmail, Qmail, and Postfix. The oldest of the three, Sendmail, was the Internet MTA (mail transfer agent) for years, and is still one of the most pervasive. Sendmail was never for amateurs, as configuration was significantly complex, nor was it built with strong security in mind. Along came Qmail, an even more powerful and flexible MTA that made security a top priority. Finally, we were blessed with Postfix. Though not as powerful and adaptable as Sendmail or Qmail, Postfix was oh-so-easy to configure, and still had the chops to perform most any task that an administrator would ask of it. These three MTAs still make up the majority of the Internet's mail servers today.
What do you do when you need access to your workstation but you're away from the office? It is, was, and perhaps always will be VNC to the rescue. VNC (Virtual Network Computing) is GPL-licensed software that gives a user remote access to a computer, much like pcAnywhere and Microsoft's remote desktop protocol. VNC was originally developed by Olivetti Research Laboratory in Cambridge, UK, in the mid 1990's. Several derivatives of the original VNC project exist, adding features such as connection encryption, lower bandwidth requirements, SSH tunneling, and even file transfers. Versions are available for various flavors of Windows, Mac OS X, and most Unix-like operating systems.
What good network or systems admin hasn't used Wireshark (formerly Ethereal) to troubleshoot a network bottleneck or a sluggish client/server application? Wireshark captures network traffic, then provides a helpful interface to analyze the data, letting you view an entire conversation between two computers down to the network packet level. Despite the presence of several big commercial tools for network protocol analysis, many top network consultants choose to use Wireshark instead.