Ubuntu Server: Lean, mean, cloud-making machine
- — 02 June, 2009 08:12
Ubuntu Server is a fast, free, no-frills Linux distribution that fills a niche between utilitarian Debian and the GUI-driven and, some would argue, over-featured Novell SUSE and Red Hat Enterprise Linux.
In our business transactions benchmarking tests, Canonical's Ubuntu Server 9.0.4 was nearly as fast as the closest Linux cousin we've reviewed recently, Novell's SUSE Linux Enterprise Server 11.
Ubuntu Server doesn't have a GUI. Instead, at installation, users have the choice of adding services, such as DNS, LAMP (Linux Apache MySQL PHP), mail, OpenSSH, PostgreSQL database, print services, SAMBA and/or TomCat Java services.
Users can also configure the server as a svelte virtual machine or manually install server applications and utilities. The installation choices are offered through a simple 'VGA' (character) graphics menu.
Ubuntu Server also includes a version of Eucalyptus -- an open source tool for implementing Linux on public and private clouds. It's compatible with Amazon's Elastic Compute Cloud (EC2), Simple Storage Service (S3) and Elastic Book Store (EBS).
Eucalyptus, based on an open source project at the University of California at Santa Barbara, is comprised of a cloud controller, a cluster controller and node controller. Together, various nodes (operating instances where the work actually happens) are tied together either in local or disparate server locations, according to the desired computational strength, and the needs of availability of the nodes to do actual work.
Since communication among the components uses SOAP, a commonly understood mechanism in application development, we found building clusters into our own cloud to be pretty simple.
These selections map to popular uses of Linux servers, and an 'OEM' installation can also be made that makes a distributable 'cut' of Ubuntu server for pre-installed application server deployments.
The OEM 'cut' can 'ask questions' of end-user installers in order to configure or setup the server via a text-based interface. Before this version, only UbuntuDesktop could use the OEM tools, as they were GUI only.
These considerations and options are reminiscent of far older VAR (value added redistributor/developer-sourced) versions of Xenix, UnixWare, and other i386/486 versions of Unix, and hints at the potential for this totally zero-cost Linux distribution.
In fact, the only thing you can buy is extended support, as the first 18 months of support are free. If 'free' wasn't enough, it's also possible to strip out (at installation) any installation of 'non-free' (closed source or non-GPL/Apache-licensed) software, which will make free open source software (F/OSS) purists tingle.
Ubuntu 9.0.4 is a headless server operating system that's best downloaded from one of many mirror sites and is delivered in the form of an ISO image. From there, it can be burned to media or installed by various virtual machine hypervisor installer applications. We tried both methods successfully.
At installation, the default file system used is ext3, which can be simply changed to ext4, ReiserFS, or even NTFS. A script guides installation, and defaults will install only minimal components, which we like.
However, when we wanted to make changes, we found some of the choices cryptic. Fortunately, each option permits IT managers to 'go back,' although contextual help is unavailable.
Instead, we looked up selections in Ubuntu's documentation, which is reasonable for non-civilian installers and comes either from online sources or a fat, downloadable PDF file.
There are two different mail/message transfer systems that can be installed (initially or later), industry stalwart postfix or exim4 . The Ubuntu Server distribution includes Dovecot, which delivers POP3 or IMAP4 mail. Delivery of mail to users and list management is performed by the GNU mailman application, which is based on Python and works with either postfix of exim4.