hi @ushasri,
The file you are looking for is called flow.xml.gz and can be found on each NiFi node, within the conf folder.
More information can be found here: https://nifi.apache.org/docs/nifi-docs/html/user-guide.html
flow.xml.gz: Everything the DFM puts onto the NiFi User Interface canvas is written, in real time, to one file called the flow.xml.gz. This file is located in the nifi/conf directory by default. Any change made on the canvas is automatically saved to this file, without the user needing to click a "Save" button. In addition, NiFi automatically creates a backup copy of this file in the archive directory when it is updated. You can use these archived files to rollback flow configuration. To do so, stop NiFi, replace flow.xml.gz with a desired backup copy, then restart NiFi. In a clustered environment, stop the entire NiFi cluster, replace the flow.xml.gz of one of nodes, and restart the node. Remove flow.xml.gz from other nodes. Once you confirmed the node starts up as a one-node cluster, start the other nodes. The replaced flow configuration will be synchronized across the cluster. The name and location of flow.xml.gz, and auto archive behavior are configurable. See the System Administrator’s Guide for further details.
