Most ISP provide Internet connections using a dynamic IP address. This address changes from time to time so is not possible to point a domain name to it because it is not fixed. Dynamic DNS allows to update the public IP address associated to a domain so you can expose services to the Internet using the known domain name: different websites, VPN for remote access or a mail server.
The free Zentyal Basic Subscription offers a zentyal.me subdomain for your server (e.g. yourserver.zentyal.me) with up to 3 additional aliases. These subdomains are available on “first-come, first-served” basis so grab your own before someone else does! On top of that you configure the MX records needed if you set up a mail server. One of the star features of Zentyal Dynamic DNS service is the multigateway support: if you have multiple Internet connections you will get a third level subdomain for each one (e.g. dsl1.yourserver.zentyal.me, dsl2.myserver.zentyal.me, etc) which will point to you main subdomain on round-robin for load balancing.
Zentyal Cloud Dynamic DNS configuration is integrated on the server administration interface and the domain management is available on your Zentyal Cloud account. You can gain access to this brand new feature by subscribing your Zentyal servers (2.1 and higher) to Zentyal Cloud with the free Basic Subscription. Currently this feature is available only for latest Zentyal beta versions which will become the next stable Zentyal version (Zentyal 2.2) in September 2011.
The Zentyal Basic Subscription is a free community subscription, aimed to be used in testing environments. It gives access to some Zentyal Cloud features and services, giving the users an idea of Zentyal Cloud functionality. Currently these features and services include: