Vnstat2, database resets after reboot

I have installed vnstat2 on my openwrt.
When i do a reboot all data resets.
Installed usb stick. (nlbwmon works fine with data stored to USB)

I have changed /etc/vnstat.conf to
# location of the database directory ;DatabaseDir "/mnt/sda1/vnstat" (folder vnstat 777 permission)
Still no sucsess.
Please anyone ?

Remove the ; from the line:

DatabaseDir "/mnt/sda1/vnstat" 

Reboot the router.


the semicolons in the vnstat.conf file are confusing.

they apparently are comments similar to hashtag, or pound sign, ( # ) and must be removed for the line to work.

this has no effect:
;DatabaseDir "/mnt/sda1/vnstat"

but this works (without semicolon):
DatabaseDir "/mnt/sda1/vnstat"

A simple comment indicating the # and also ; behave as comments would be helpful in the /etc/vnstat.conf file.

that's why @powtrix said the ; should be removed ?