Zend Server Licensing On Docker and Virtual Machines


This article is also available in our new Knowledge Base: Zend Server Licensing On Docker and Virtual Machines


This article should help clarify some questions regarding licensing Zend Server in a multi machine environments.

Modern Zend Server users and DevOps, who utilize many virtual containers for services and applications, are concerned about legality of licensing multiple instances with the same license.

EULA overview

Production license

– according to the EULA, usage scope covers license target machines as the order entitles, meaning:

Number of units per license = Number of allowed installations to register.

So if you have a license for a single unit, or single server, you can legally register only one VM, or instance, or container, with this license. This is not related to number of CPU cores utilized by the machine. If you own a license for 3 servers, or units, you can register up to 3 separate installations with it, or, you can join a Zend Server cluster of maximum 3 nodes, sharing the same OS, PHP configuration, applications and centralized management (UI, automation and backend tasks).

Developer license

– any number of Zend Server installations can be made by / for a developer which the license is assigned to. The license in this case "sticks" to a developer, not a machine.

Any additional developer working on those Zend Server machines, requires an additional license assigned to him / her (not re-registered, but legally purchased and assigned). Also, Developer License prohibits any type of serving real users or any production use, including acting as a production web service, reporting generator, and so on.


Q: How many Docker containers can I register with my license?

A: Going by the Production/Developer types depicted above, with a production license holding a single unit - only a single Docker container can use the license. For any additional Docker production servers more "units" needs to be purchased.
With a developer license, single developer can raise AS MANY Docker containers for development, on as many hosts, as long as he / she is the sole developer utilizing those instances.

Q: Do I need to "un-register" a Zend Server installation before registering another with the same license?

A: When you install Zend Server on any machine, you get Enterprise Trial version (with clustering) for 30 days. At this stage, you can either prepare your new server and later on register it and uninstall Zend Server from the old server, or, if you wish to register the correct edition (for example, a limited Small Business license), you can ask our support team for a temporary license for a week or two and migrate to the new server which is registered with your regular license. There is another option which is to copy the trial license off the new server and replace it on the old server, this way the old server will have 30 days and the regular license is free for the new server.

Q: Can I pre-install Zend Server on backup machines, to quickly put in load balancing when there is a peak on my website / application, or when an active server goes down?

A: You can always contact Zend account manager to discuss a quote for backup licenses according to your architecture requirements. You can also create a cluster, where multiple servers are always available, and updated live with any configuration changes and new applications and their resources, but not serving your applications (out of the load balancer). The only traffic coming to/from those idle cluster nodes is related to Zend Server management and those live configuration changes, in some cases this is a very good approach for companies with limited traffic.

If you have additional licensing related questions, please consult with your Zend account manager, or using the chat system / icon in our website.

For licensing technical problems please open a support ticket with the software information, license details and errors or functionality problems, so we can assist accordingly.