A Configuration in the BMC Middleware Automation product is an XML document that describes all or part of an application server's configuration. It is an external representation of configuration values that are displayed through an application server's administrative console. BMC has created an XML schema for each supported application server so that, using BMC Middleware Automation, you can retrieve a Configuration from an application server, view it, compare it with other Configurations, modify it, and install it on the same or other application servers.
A Snapshot is a Configuration retrieved from a server at a point in time. BMC Middleware Automation connects to the application server using the connection information in the Server Profile, queries the server, and saves the current configuration in an XML document.
You can compare two Snapshots taken at different times from the same server to see what has changed in the server's configuration. You can compare Snapshots taken from different servers to see the differences in their configurations and isolate the difference that is responsible for a problem that is occurring on one server. Saving a series of Snapshots for a server enables you to audit configuration changes. When troubleshooting your environment, an audit trail of changes is invaluable. It can help you to identify the exact change that introduced a problem. Furthermore, reinstalling an earlier Snapshot is an easy way to roll back the configuration while the problem is being fixed.
You can modify a Snapshot to create a custom Configuration. You can install a custom Configuration on a server as an alternative to using the server's administrative console. For example, if you want to change a server's listen port, you can take a Snapshot, edit the port number in the Snapshot (thereby creating a custom Configuration), and then reinstall the Configuration on the application server. BMC Middleware Automation compares every value in the Configuration document with the current server configuration, changing only the values that you modified.
To make installing a Configuration more efficient, you can create a custom Configuration that contains only the elements that you want to change on the server. During the installation, BMC Middleware Automation analyzes only those values that exist in your custom Configuration, so that your modifications can be isolated. Creating targeted custom Configurations reduces the likelihood of introducing side-effect problems.
Working with Snapshots and Configurations includes the following tasks:
For additional instructions on modifying the contents of a Configuration in preparation for installation operations, see Preparing Configurations for installation operations.
Another method for capturing and viewing application server configuration is described in Creating and viewing application server configuration diagrams.