Zend - The PHP Company

Zend Server Frequently Asked Questions

Editions & Licensing


Application support


Q: What are the differences between the free edition and the paid editions of Zend Server?

Zend Server Free Edition has most of the same features of the paid editions of Zend Server (Enterprise, Professional, and Small Business). The primary differences are that the free edition has a much shorter metric and event retention period and is supported only via online forums, making it great for development but unsuitable for production use. Learn more about the differences between the various editions of Zend Server.

Q: Can I upgrade from the free edition to a paid edition of Zend Server?

Yes, you can easily upgrade by entering a paid license in the Zend Server administration screen. Talk to a Zend expert about upgrading.

Q: How is Zend Server Free Edition different from a purely open source PHP stack or from xampp?

While they are all free, Zend Server Free Edition provides many additional features to help PHP developers and sysadmins write, deploy, and manage applications. Those features include a certified, tested PHP runtime pre-configured with popular extensions and libraries, advanced debugging tools, monitoring and performance dashboards, and more. See more information on the differences between Zend Server Free Edition and other free PHP options.

Q: Which Zend Server editions support clustering applications onto multiple servers?

Running highly available applications that are clustered across multiple servers requires Zend Server Enterprise or Professional editions. Learn more about the differences between the various editions of Zend Server.

Q: For multiple server environments, how many licenses will I need?

You need one license for every instance of Zend Server in the cluster, regardless of how many physical or virtual machines the cluster is actually running on or the number of CPUs used by those machines.

Q: What are the differences between Zend Server 6 and older versions?

Zend Server 6 puts an emphasis on deploying, managing, and monitoring PHP applications, a more granular capability than managing PHP servers. It also has a newly designed user interface with dashboards and performance charts, enterprise security and compliance features, a more cloud-friendly architecture, and more.

Q: Can I upgrade to Zend Server 6 from a previous version of Zend Server?

Yes. For more details, see the installation and upgrade guide for your operating system:

Q: I want to upgrade from Zend Server 5.6 Production Solution - what happened to the Cluster Manager in Zend Server 6?

Zend Server 6 uses a new, more cluster-friendly architecture that does not require a Cluster Manager. All nodes in a Zend Server 6 cluster are identical, and are kept in sync via database.

Q: Can I take advantage of application-specific features without having to use Zend Server to redeploy my existing applications?

Yes. Existing URLs on your server can be defined as applications, allowing you the same monitoring and management capabilities as applications deployed through Zend Server.

Q: What platforms and web servers are supported for application deployment?

Zend Server supports application deployment on both Linux and Windows. Application deployment is only supported using the Apache web server.

Q: Can I automate the installation of Zend Server using Puppet or Chef?

Yes, via Zend Server's Web API it is fully possible to not only install Zend Server, but also set passwords and licences. Furthermore, when working in a clustered environment, it is also possible to automate the joining of a new cluster node to a running cluster. Given that the Web API is available via command line calls this can easily be integrated into Chef/Puppet scripts.

Q: What is a document root?

The document root is the file system directory in which files need to be placed in order to be run by the Web server. Files placed in your document root can be accessed by browsing to http://localhost:<port_number>/<file_name>. Files and directories under the document root will generally be available for download (if they are static files such as HTML or images) or for execution (if they are dynamic files such as PHP scripts).

Q: Where is my document root?

The location of your default Zend Server document root depends on the operating system and the Web server you are using:

  • On Microsoft Windows:
    • If Zend Server is running on Microsoft IIS - C:/inetpub/wwwroot
    • If Zend Server is running on Apache - C:/Program Files/Zend/Apache2.2/htdocs
    • If you changed the location of your Zend Server installation, your document root will be located at <Zend_Server_installation_directory>/Apache2.2/htdocs, where <Zend_Server_installation_directory> is the location of the directory in which your Zend Server is installed.
  • On Linux: the location of your document root is defined by your distribution's Apache packages, and will vary depending on your distribution and configuration.
    Common locations include:
    • Debian, Ubuntu - /var/www
    • Fedora Core, RHEL, CentOS, Oracle Enterprise Linux - /var/www/html
  • On Mac OS X: /usr/local/zend/apache2/htdocs

Q: What is my port number?

In most cases, your Web server's port number will be 80. If your port number is 80, you can omit the <port> parameter from your URL when browsing to your Web pages (i.e. you can browse to http://localhost/<file_name> without specifying a port number).

In the following circumstances, your port number will be different:

  • You are running Zend Server on Mac OS X. In this case, the default port number will be 10088.
  • You modified the port number on which Zend Server listens, during or after installation.

Q: What is the expected improvement in performance with Zend Server?

Zend Server provides multiple technologies (code acceleration, full page caching and data caching) to improve your application response times and minimize resource utilization. Many customers report performance boosts of 200-300% for typical PHP applications, with reduced resource utilization.

Q: How can I install Zend Server using my existing Apache Web server?

In Windows, Zend Server bundles its own Apache Web server and cannot use an existing pre-installed Apache server.  
On Linux, Zend Server uses the Apache server which is shipped with the Linux distribution.

Q: I am trying to add a custom PHP extension (as a DLL) on Windows, but the extension does not load. Why is that?

Before trying to add pre-built binary extensions on Windows, please make sure that the extension is built for the PHP version that is shipped with Zend Server, that it is not a debug build, and most importantly, that the extension is compiled in non-thread-safe (NTS) mode. Extensions compiled with thread-safety enabled will not work with Zend Server. Please note that Zend does not support custom extensions, and that before submitting any support requests, you should disable any custom extensions that you have added.

Q: What is the 'Web server user'?

When the Web server starts up, its processes will run as a particular user. You can use this user to set permissions for the Web server and PHP to write to various system resources.

The following are the default user values.  If you have modified your configuration, use the modified values:

On Windows:
  • If Zend Server is running on Microsoft IIS - IUSER
  • If Zend Server is running on Apache - SYSTEM
On Linux:
  • DEB installation - www-data
  • RPM installation - apache
    • Debian, Ubuntu - /var/www
    • Fedora Core, RHEL, CentOS, Oracle Enterprise Linux - /var/www/html
On Mac OS X: daemon

Q: How does Zend Server pricing account for virtualization or for machines with multiple cores?

Zend Server is priced per server instance, regardless of the physical or virtual nature of the hardware or the hardware CPU configuration.


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Customer Quote

   Leveraging Zend Server’s capabilities and SDK allowed us to simplify the scripting and packaging mechanisms for the deployment of our code and to effortlessly support server clusters, enabling non-expert users to initiate deployments. This ensured extra control and the flexibility essential for Novadex to stay at the forefront of cloud based business communication management.   

Andreas RossbachCTO, Novadex

   Our provisioning scripts and the fully laid-out functionality of Zend deployment eliminated a lot of manual processes. Between Zend Server and Zend’s ongoing support, we’ve also gotten a lot of experience on how to do better performance testing.   

Luis ColonDirector of Enterprise Architecture, CDS Global

   With Zend Server, you can have multiple applications running on the same server, whereas other models allow just one application per server. This translates into cost savings for us because our development QA testing server has 12 apps running on it in parallel, and with Amazon Cloud our server costs are our biggest expense.    

Jonathan MarstonVice President of Engineering, EnglishCentral