Your question is pretty general which is why you probably have not received any responses... The L3 config file is a very important file - it is typically 10K or more lines of JSON. You can unload, modify and reload it. Be sure to keep a backup!!!
The master data itself is stored in the Graph DB that Reltio talks about extensively. The physical implementation of the Graph DB depends on the specific cloud in which you run.
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[Daniel] [Condreay] [PMP]
[Sr. Systems Analyst]
[Symetra]
[Bellevue] [WA]
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