A big German ISP (Telekom) recently decided to volume limit their DSL internet connection to 75GB per month.
Now I would like to know how much I download / upload. I use Linux Mint 14 Nadia and I have a D-LINK DI-524 router.
How can I get the amount of data I upload / download per month?
If you're looking for a user-friendly GUI app I'd recommend download monitor. You can view stats, assign quota etc.
A simple, nice CLI alternative is vnstat (howto).
vnstat -m to see a monthly breakdown. I really think this is the tool for the job, personally. The output from ifconfig contains packet and byte counters, normally listing the count since the system was booted up.
The information is also available in /proc/net/dev in a somewhat more machine-readable format.
It's also worth noting for completeness' sake that some routers (a specific example being my Cisco small-business-geared model) provide information through their administration interfaces about how much data has been transferred. Mine can be configured to reset the counters at a specified interval, email reports and implement limits in addition to simply displaying the numbers in its web interface.
I have no idea if the DI-524 specifically has such capabilities, but it might be worth having a look through its administration interface just in case. Since the router is generally restarted much more rarely, it would probably provide relatively useful data, and it also won't be limited to one particular host, which may or may not be of interest.
There are many ways one is you just download vnstat.
apt-get install vnstat then first set up
vnstat -u -i eth0 vnstat -u -i wlan0 After that you have to type this command in terminal to know the status
vnstat -m 