With the implementation of Single Fix 8218568 there is a misconception that all the environmental based settings are now externalized. This is not the case there are two more locations where there are some additional environmental settings:
- web.xml - The J2EE Application Descriptor
- XAI Options - MPL and other XAI components use this as a registry
The product can (and does) support clustering if you set these settings correctly. Let me explain.
There are four types of environmental setting that are left in these files and here some advice on how to set them in a clustered environment:
- Hostnames - Hosts for URL are used. In a clustered environment, this value should be set to the cluster host or the proxy host/load balancer.
- URL Patterns - It is possible to change the URL pattern (i.e. SPLApp/cis.jsp) to allow flexibility in the URL. In most clusters this value is common across the cluster, therefore any value you specify should apply to all nodes in a cluster.
- Port Numbers - The port number is specified as part of the URL. Most sites tend to use 80 in production as that is the default port. Again, in most clusters this value is common across the cluster, therefore any value you specify should apply to all nodes in a cluster. Most vendors require a cluster to use a common port number across the cluster. If the port number changes per node, that is typically called "managed" servers not "clustering".
- File Locations - Some of our components need to orientate where key files are stored. In a cluster it is assumed that the underlying software has been installed on each of the nodes. If this is not the case this value can be set to a shared resource on the cluster that holds that information. If the software is installed then to support clustering the software should be installed in the same location across the cluster.
Setting these values appropriate can assist in supporting clustering with environmental settings.
