VNSTAT(1) User Manuals VNSTAT(1)
NAME
vnStat - a console-based network traffic monitor
SYNOPSIS
vnstat [ -Ddhlmqrstuvw? ] [ -i interface ] [ -tr time ] [ --cleartop ]
[ --config file ] [ --days ] [ --debug ] [ --disable ] [ --dumpdb ] [
--enable ] [ --help ] [ --hours ] [ --iface interface ] [ --live ] [
--longhelp ] [ --months ] [ --nick nickname ] [ --query ] [ --rebuild-
total ] [ --reset ] [ --short ] [ --showconfig ] [ --testkernel ] [
--top10 ] [ --traffic time ] [ --update ] [ --version ] [ --weeks ]
DESCRIPTION
vnStat is a console-based network traffic monitor. It keeps a log of
hourly, daily and monthly network traffic for the selected inter-
face(s). However, it isn’t a packet sniffer. The traffic information is
analyzed from the proc(5) filesystem. That way vnStat can be used even
without root permissions.
OPTIONS
-d, --days
Show traffic for days.
-h, --hours
Show traffic for the last 24 hours.
-m, --months
Show traffic for months.
-s, --short
Use short output mode. This mode is also used if more than one
database is available.
-t, --top10
Show all time top10 traffic days.
-w, --weeks
Show traffic for 7 days, current and previous week.
-tr time
Calculate how much traffic goes through the selected interface
during the given time seconds. The time will be 5 seconds if a
number parameter isn’t included.
-l, --live
Display current transfer rate for the selected interface in real
time until interrupted. Statistics will be shown after interrup-
tion if runtime was more than 10 seconds.
-i, --iface interface
Select one specific interface and apply actions to only it.
-q, --query
Force database query mode.
-u, --update
Update all enabled databases or only the one specified with -i
parameter.
-r, --reset
Reset the internal counters in the database for the selected
interface. Use this if the interface goes down and back up, oth-
erwise that interface will get some extra traffic to its
database.
--sync Synchronize internal counters in the database with interface
counters for the selected interface. Use this if the system is
rebooted but interface counters aren’t reseted. Such can occur
when suspend to ram/disk is used.
--enable, --disable
Enable or disable updates for selected interface. Useful for
interfaces that aren’t always available, like ppp0. If the
interface goes down it should be disabled in order to avoid
errors. Add something like vnstat -r --disable -i ppp0 to the
script that’s executed when the interface goes down and vnstat
--enable -i ppp0 to the up script.
-v, --version
Show current version.
--cleartop
Remove all top10 entries.
-?, --help
Show a command summary.
--longhelp
Show complete options list.
--nick nickname
Set the selected interfaces nickname as an alias the will be
displayed in queries. Usage of -u is required to save the
change.
--config file
Use file as config file instead of using normal config file
search function.
--rebuildtotal
Reset the total traffic counters and recount those using
recorded months.
--testkernel
Test if the kernel boot time information always stays the same
like it should or if it’s shifting.
-D, --debug
Show additional debug output.
--dumpdb
Instead of showing the database with a formated output, this
output will dump the whole database in a format that should be
easy to parse with most script languages. Use this for example
with PHP, Perl or Python to make a custom webpage. The dump
uses ; as field delimeter.
active;1 activity status
interface;eth0 name for the interface
nick;inet nick (if given)
created;1023895272 creation date in Unix time
updated;1065467100 when the database was updated
totalrx;569605 all time total received MB
totaltx;2023708 all time total transmitted MB
currx;621673719 latest rx value in /proc
curtx;981730184 latest tx value in /proc
totalrxk;644 total rx kB counter
totaltxk;494 total tx kB counter
btime;1059414541 system boot time in Unix time
Then follows 30 lines like the following
d;0;1078696800;559;7433;68;557;1
where d = days, 0 = day number in database (0 is today),
1077314401 date in Unix time, 559 = rx MB, 7433 = tx MB, 68 = rx
kB, 557 = tx kB and 1 tells that vnStat has filled this value
and it is in use.
m;0;1078092000;48649;139704;527;252;1 (x12)
t;0;1078351200;5979;47155;362;525;1 (x10)
h;0;1078699800;118265;516545 (x24)
m = months, t = top10 and h = hours, all other fields are in the
same order as in days except hours that doesn’t have a separate
kB value. For hours the forth and fifth fields have values in
kB.
FILES
/var/lib/vnstat/
This directory contains all databases the program uses. Files
are named according to the monitored interfaces.
/etc/vnstat.conf
Config file that will be used unless $HOME/.vnstatrc exists.
EXAMPLES
vnstat -u -i interface forces a database update for interface or cre-
ates the database if it doesn’t exist. This is usually the first com-
mand used after a fresh install.
vnstat -u -i interface --nick nick gives interface the nickname nick
and that information will be later included with queries.
vnstat -u -r --disable -i interface resets the internal counters of
interface and disables it from being updated before enabled again with
the --enable parameter. This feature is especially useful for inter-
faces like ppp0 that aren’t always active.
RESTRICTIONS
Updates needs to be executed at least as often as it is possible for
the interface to generate enough traffic to wrap the kernel interface
traffic counter. Otherwise it is possible that some traffic won’t be
seen. This isn’t an issue for 64 bit kernels but at least one update
every hour is always required in order to provide proper input. With
32 bit kernels the maximum time between two updates depends on how fast
the interface can transfer 4 GB. Calculated theoretical times are:
10 Mbit: 54 minutes
100 Mbit: 5 minutes
1000 Mbit: 30 seconds
However, for 1000 Mbit interfaces updating once every minute is usually
a working solution.
Estimated traffic values are likely to be somewhat inaccurate if daily
traffic is low because only the MB counter is used to calculate the
estimate.
Virtual and aliased interfaces can’t be monitored because the kernel
doesn’t provide traffic information for that type of interfaces. Such
interfaces are usually named eth0:0, eth0:1, eth0:2 etc. where eth0 is
the actual interface being aliased.
AUTHOR
Teemu Toivola <tst at iki dot fi>
SEE ALSO
proc(5), ifconfig(8)
version 1.6 JANUARY 2008 VNSTAT(1)
