It keeps a log of hourly, daily and monthly network traffic for the selected interface(s) but is not a packet sniffer.

This means that vnStat won't actually be sniffing any traffic and also ensures light use of system resources.

vnStat had an Initial public release in 23-Sep-2002 (version 1.0) by Teemu Toivola.

[5] Nowadays Debian keeps a full history[6] about vnstat by using a Rich Site Summary.

On 26 April 2012 was included in Ubuntu 12.04 Precise Pangolin[7] On 16 February 2017 a 1.17 version was released.