It's a disabled-by-default exporter: https://github.com/prometheus/node_exporter/#disabled-by-default
Yes, you have to enable it with a command line flag. https://github.com/prometheus/node_exporter/#collectors Collectors are enabled by providing a --collector.<name> flag. Collectors that are enabled by default can be disabled by providing a --no-collector.<name> flag. -- You received this message because you are subscribed to the Google Groups "Prometheus Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/prometheus-users/83609a68-7800-4fe1-b6ce-3b17227a6fdf%40googlegroups.com.

