If Max_Config_Files is reduced, then the appropriate number of files is deleted.
This variable is checked only when the server starts or if there is a configuration change. If the variable Max_NSDInfo_Files exists, its value is used instead of Max_Config_Files.
The Server polls every 5 minutes for changes in the local server document and applicable configuration document(s). If it detects a change then the new document is saved as an XML file in the support directory. The oldest file is automatically deleted. The default is 10 docs, but can be changed with the ini variable MAX_CONFIG_FILES
Look for file(s) named serverdoc*.dxl and config*.dxl if you ever need them.
Note: You can also use the server console command "save noteid xxxx" to save individual documents from the Domino Directory (names.nsf) as dxl files.