This feature is same in version 8 except that the config.xml being copied and cached in the managed server is stored as msi-config.xml.
In version 9 the feature is still the same except that the complete config directory that contains the configuration file is copied by default to the managed servers. But some other files like the security (*.dat) file is not copied until the MSI file replication enabled option is ON.
Version 10 alleviate all the pains by making MSI mode and MSI file replication as a default option. So out of the box a managed server is enabled to run in independence mode. And all the files required to start a managed server by itself (/config dir and *.dat file) will be automatically copied to the managed server during startup and will be synced (automatically) with the master copy (in Admin Server).
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