I have a mobile gateway connected to my VPN via OpenVPN and a 2G connection. Now I observe some unexpected traffic (~20MB / day) and wonder where it comes from. While I'm connected to the gateway I see most traffic flowing to my VPN Server (but that might also be my active connection).
So my question is: what is the average traffic caused by OpenVPN when my gateway is connected to the VPN but not sending data through it?
I do not have
redirect-gateway def1 enabled.
To monitor real time traffic I used
iftop; for long time monitoring the OpenWRT on my gateway does not have any of these packages available:
wrtbwmon, vnstat, YAMon, luci_app_statistics, bandwidthd, ntop
Any hints how to find our where my traffic comes from (IP, Port, Process) in the long term would also help me a lot.