What does this ERROR message mean?

This error means the streaming session between two nodes encountered an error that was not a SocketTimeoutException or EOFException.

Why does this ERROR occur?

This error message acts as a catch-all for any other thrown exception aside from the two mentioned above. The actual cause will need to be investigated further.

How do you fix this ERROR?

In order to fix the error, special attention should be paid to the actual exception listed at the end of the error message. The error message will list the Streaming session planID, the peer endpoint information that the node had an exception with, and may include the through path from this node to the other. After this info, the exception and stack trace will be listed. Use that information to troubleshoot the cause. DataStax support can assist if needed.