The Servlet Specification version 2.4 states in section SRV.3.2:
The specification further clarifies the distributed scope of ServletContext attributes in section SRV.3.4.1:
Coherence*Web is fully compliant to the Servlet Specification, and as a result, it does not cluster ServletContext attributes by default. However, it does have an option to allow ServletContext attributes to be shared across multiple JVMs. Using this option, only those attributes which can be successfully serialized will be shared across multiple JVMs.
To configure the ServletContext to be clustered, edit the coherence-web.xml that is produced from the inspection step of the Coherence*Web Installer. Set the coherence-servletcontext-clustered parameter to true.