Fix RemoteTransportException

✅ Solution

RemoteTransportException in Elasticsearch, especially with NotSerializableExceptionWrapper or UnknownHostException, usually indicates a network connectivity problem or DNS resolution failure when Elasticsearch tries to communicate with a remote resource like Google Cloud Storage. Ensure your Elasticsearch nodes have proper network access (firewall rules) to the remote host and that DNS resolution is correctly configured on those nodes so they can resolve the hostname (e.g., storage.googleapis.com) to an IP address. Check `/etc/resolv.conf` and network configurations.