@nmargosian The swap file in questions would contain FlowFiles that belong to a connection with the UUID of: 7cde3c5c-016b-1000-0000-00004c82c4b2 From your Flow Configuration history found under global menu icon in upper right corner, can you search for that UUID to see fi there is any history on it? - Do you see int existing at some point in time? Do you see a "Remove" event on it? - If you see it in history, but there is no "Remove" action, but it is now gone, then the flow.xml.gz loaded on restart did not have this connection in it. If this connection no longer exists in the canvas, NiFi can not swap these FlowFiles back in. Everything you see on the canvas resides in heap memory and is also written to disk within a flow.xml.gz file. When you stop and start or restart NiFi, NiFi loads the flow back in to heap memory from the flow.xml.gz (each node has a copy of this flow.xml.gz and all nodes must have matching flow.xml.gz files or nodes will not rejoin the cluster. Things I suggest you verify... 1. Make sure that NiFi can successfully write to the directory where the flow.xml.gz file is located. Make a change on the canvas am verify the existing flow.xml.gz was moved to the archive directory and a new flow.xml.gz was created. If this process fails then when NiFi is restarted any changes you made would be lost. For example the connection was created and data was queued on it, but NiFi failed to write new flow.xml.gz because it could not archive current flow.xml.gz (space issues, permissions/ownership issues...etc). This would block NiFi from creating a new flow.xml.gz, but the flow in memory would have your current flow still. All these directories and files should be owned and readable/writable by your NiFi service user. 2. Did some point in history did your cluster nodes fllows mismatch. For example, a change was made on the canvas of a node that was currently disconnected from the cluster. Then that nodes flow was copied to the other nodes to make all nodes in sync. 3. Was an archived flow reloaded back to NiFi at some point. This requires manual user action to copy a flow.xml.gz out of archive and used to replace the existing flow.xml.gz. NiFi restarts will not just remove connections from your dataflows. Some other condition occurred and it may not have even been recent. If you hav enough app.log history covering multiple restarts, do you see this same exact warn log line with each of those restarts. Hope this helps, Matt
... View more
