@digs did the trick. I was not able to log in, uninstalled and insalled lot of times, updated pfsense from 2.4.4_3 to 2.4.5, same scenario not able to login (login loop).
Deleted all on /var/db/ntopng/, unistalled on gui, reinstalled then working. Thank you!
I've got the same question -- I really like all the data that ntopng can provide, but it's killing my SSD due to all the frequent writes of RRD data. Darkstat is not as useful as I can't map external traffic IPs to internal ones.
I did enable a ramdisk for /tmp and /var (System -> Advanced -> Miscellaneous) but would rather not do that if I can find another option.
I definitely agree on volume / time / bandwidth.
The issue is nprobe is not free, but I saw an option to send flows to an ELK.
In the meantime, trying scrutinizer, elastiflow and others.
But at least, I know what i'm looking for is not embedded in Pfsense.
@jimp I believe there to be two quirks - vnstat outputting March and not April (though I do understand if that is due to accumulation of data due to non 1 start day), but the fact that vnstat output shows march and the traffic totals show Feb I believe is an issue in status_traffic_totals.php as it does not reflect March as vnstat does. I traced the code and saw it correctly fetches the march entry, but then it changes the date to Feb 29 18:00 or something, which is my PST shift.