$ curl cheat.sh/
 cheat.sheets:vnstat 
# vnstat
# Network traffic monitor that keeps a log of daily network traffic.

# Display a summary of the current month's network traffic
vnstat -m

# Display a summary of the traffic for the current day
vnstat -d

# Show the hourly traffic usage for a specific day
vnstat -h

# Display real-time traffic statistics
vnstat -l

# Display a live, continually updating traffic report
vnstat -tr

# Export all data in JSON format
vnstat --json

# Display traffic statistics for a specific network interface
vnstat -i eth0

# Reset all data for a specific interface (caution: this deletes all recorded data)
vnstat --reset -i eth0

# Display traffic statistics in kilobytes
vnstat --unit k

# Display detailed help for vnStat options
vnstat --help

 tldr:vnstat 
# vnstat
# A console-based network traffic monitor.
# More information: <https://manned.org/vnstat>.

# Display traffic summary for all interfaces:
vnstat

# Display traffic summary for a specific network interface:
vnstat -i eth0

# Display live stats for a specific network interface:
vnstat -l -i eth0

# Show traffic statistics on an hourly basis for the last 24 hours using a bar graph:
vnstat -hg

# Measure and show average traffic for 30 seconds:
vnstat -tr 30

$
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