Zentyal Linux small business server

Zentyal (formerly eBox Platform) is a Linux Small Business Server that can act as a Gateway, UTM, Office Server, Infrastructure Manager, Unified Communications Server or a combination of them. Zentyal offers an easy-to-use web interface to manage all your network services, from Internet access, network security, resource sharing, network infrastructure or communications.

Zentyal is the open source alternative to Windows Small Business Server and it is being widely used in the small and medium businesses regardless of sector, industry or location as well as in the public administrations or in the education sector. It is estimated that there are over 50,000 active Zentyal installations all over the globe.

Zentyal Migration Tool for Windows Server is also available for download, making the migration process from existing Windows environments easier.

Zentyal development is funded by eBox Technologies that offers commercial support and cloud-based services on top of Zentyal server.

Features
Gateway: transparent caching, load balancing, traffic shaping, content filtering...
UTM: firewall, IDS, VPN management, antispam, antivirus, ...
Infrastructure management: DHCP, DNS, NTP, certificates, ...
Office server: LDAP, PDC, file & printer sharing, backup, groupware, ...
Unified Communications: email, IM, VoIP
LDAP replication and Windows Active Directory synchronization

Download from here
http://www.zentyal.org/downloads/
Visit Website -
http://www.zentyal.org
Installation -
http://doc.zentyal.org/en/installation.html
Screenshot -