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The Turnkey Linux Virtual Appliance Library is an open source project developing a free virtual appliance library of pre-packaged servers based on Ubuntu that deploy on bare metal, a virtual machine, and in the cloud.
The project's slogan is Best of open source, simplified!
Each virtual appliance is a ready-to-use solution that's optimized for ease of use in server-type usage scenarios.. Unlike a conventional server installation, an appliance is designed to "just work" with little to no configuration required.
The project currently maintains 40 virtual appliances, which are packaged in multiple build formats:
Founded by engineers of an Israeli startup, the project was conceived in mid-2008 as a community oriented open source project that would focus on helping users intelligently piece together turnkey solutions from open source components in the largest Linux distributions. According to one of TurnKey Linux's co-founders, the project was in part inspired by a desire to provide open source alternatives to proprietary virtual appliance vendors, that would be aligned with user interests and could engage the community.
In September 2008, the project released three prototype appliances for Drupal, Joomla and LAMP, based on the Ubuntu 8.04.1 build. Two months later, a usability focused batch of appliances was released in response to user feedback. In this release a new configuration console written for this purpose was
added along with a web administration interface.
In the following months more beta appliances were released, and by the end of February, 2009 the range included Ruby on Rails, MediaWiki and Django. In early March, 2009, TurnKey Linux released a new batch of appliances, 12 in total, re-engineered on top of a new TurnKey Core base.
In October 2009, the project released new versions of 40 appliances based on Ubuntu 8.04.3 including 25 new additions to the virtual appliance library. The release included support for Amazon Elastic Compute Cloud, and a new Virtual Machine image format with OVF support.
Design
TurnKey's virtual appliances are a series of "stripped down" versions of Ubuntu. To this they add the TurnKey Core, which includes all the common features for the project's virtual appliances, including:
di-live: a live installer, derived from debian-installer, which is unique to the project. The installer is designed to facilitate installation of an appliance to a host machine faster (for example, in about 60 seconds) than conventional package based installers.
A configuration console: developed from scratch in Python for the project to allow users to perform basic configuration tasks (for example, networking configuration, reboots)
An automatic mechanism that installs security patches on a daily basis.
Web administration interface based on Webmin which includes a selection of generically useful add-on control and configuration modules.
The TurnKey Core has a footprint of approximately 110 MB, and is available as a separate download. Application software is installed on top of the Core, which typically increases the size of a virtual appliance up to approximately 160 MB. By downloading and installing the appliance package to the hardrive, it is intended by the developers that administrators would gain an easy method of setting up a dedicated server.
TurnKey's virtual appliances can be customized and extended using TKLPatch, a simple appliance modification mechanism. New virtual appliances can be built as high-level patches to the closest starting point in the library.