If you’ve got this error, this is probably because you are using the sintax of an old configuration file. This is solved by modifying the configuration file and instead of using one dash using two!

Look two dashes!!!
ARGS=”—collector.diskstats.ignored-devices=^(ram|loop|fd)\d+$ \
—collector.filesystem.ignored-mount-points=^/(sys|proc|dev|run)($|/) \
—collector.textfile.directory=/var/lib/prometheus/node-exporter”