TurnKey
Zimbra Appliance is a free open source solution that just works. It gets you up and running with Zimbra in minutes on a virtual machine, bare metal or in the cloud.
Highlights:
- Easy to use: includes a configuration console and web management interface.
- Lightweight: built from the ground up with the minimum required components.
- Runs everywhere: available as VMDK with OVF support, installable Live CD, and Amazon EC2 AMI.
- 100% open source: free from expensive and restrictive proprietary licensing.
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About TurnKey Linux: best of open source - simplified
The largest Linux distributions have over 23,000 packages which are free for both commercial and non-commercial uses, including updates. However, currently it can still take considerable skill and effort to cherry-pick the right components and glue them together into a compelling solution.
To help unlock this potential we started TurnKey Linux, an open source project developing a free virtual appliance library that features the very best open source software.
Plus, if we don't have just what you need appliances can easily be customized and extended using TKLPatch, a simple appliance modification mechanism that allows everyone to join in on the fun and satisfy the long tail of special needs. New appliances can quickly be built as patches to the closest starting point in the library.
It's easy because even our most basic appliance, TurnKey Core includes all of the standard features such as SSL support, AJAX web shell, and a rich web administration interface. In just 100MB!
TurnKey Linux Virtual Appliance Library
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TurnKey Linux release free Zimbra appliance that is easy to use and lightweight 
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