The fact that a new node is acting as a coordinator suggests that (1) you are adding a node to a DC that is taking traffic from the app, and (2) you are likely adding the node using nodetool rebuild instead of the standard bootstrap method.
If you are adding a node using the rebuild option (with auto_bootstrap set to false in cassandra.yaml), the node joins the cluster as a normal node except it doesn't have any data to serve read requests but it will accept writes. This isn't a recommended way of adding nodes to a DC that is actively serving requests from the app. As I understand only coordinator nodes generates hints files. Is > cluster uses this node as coordinator before complete join? > Or this process is normal for joining and seen as repair? > The fact that the new node is storing hints is a concern because it indicates that other nodes in your cluster are unresponsive or down. You need to investigate why that is the case. > By the way, files not deleted after 3 hour period. The node will collect hints for other nodes for 3 hours (default). If the replica has not come back online after 3 hours, hints will no longer be stored but it doesn't delete the hints but instead hand it off to the respective replica when it comes back online. Cheers!
