Server installation

Do not use a shared server. OpenCms is Java-based and you need to run a JVM on the server. Furthermore, OpenCms will keep a lot of information in the memory of the server, if you want to run a well performing website. Therefor, we do not recommend using a shared server - OpenCms will constantly allocate system resources.

Memory is the most important performance factor. Memory is much more influential than CPU speed. It is recommended to have at least 512MB of memory available.

While in most common scenarios all elements of an OpenCms installation (OpenCms itself, the DBMS, web server and servlet container) will reside on one computer. Sites expecting heavy traffic will probably need a clustered configuration where the load is distributed across more than one computer. For a clustered installation use the Alkacon OCEE Cluster Manager.

We will just mention which software components are necessary and recommended for an OpenCms installation on a server. To get information about the currently recommended version see here.

We recommend to use the latest LTS release of Ubuntu Server and install the Java SE Development Kit.

The most suitable choices are MySQL or Oracle. We recommend installing MySQL.

We recommend to use Apache Tomcat as servlet container.

We advise to use the Apache 2.4 as web server for the OpenCms installation. A Tomcat servlet container can be put behind an Apache web server using the AJP protocol, which carries all request information from Apache to Tomcat. There are two implementations of AJP module:

• mod_jk which must be installed separately
• mod_proxy_ajp which is a standard module since Apache 2.2

They both use protocol AJP, so they both provide the same functionality.