Provided by: vnstat_2.6-1_amd64 

NAME
vnstat - a console-based network traffic monitor
SYNOPSIS
vnstat [-5bDedhlmqrstvwy?] [--add] [--begin date] [--config file] [--days [limit]] [--dbdir [directory]]
[--debug] [--end date] [--fiveminutes [limit]] [--help] [-hg] [--hours [limit]] [--hoursgraph] [-i
interface] [--iface interface] [--iflist] [--json [mode] [limit]] [--limit limit] [--live [mode]]
[--locale locale] [--longhelp] [--months [limit]] [--oneline [mode]] [--query] [--rateunit [mode]]
[--remove] [--rename name] [-ru [mode]] [--setalias alias] [--short] [--showconfig] [--style number]
[--top [limit]] [-tr [time]] [--traffic [time]] [--version] [--xml [mode] [limit]] [--years [limit]]
DESCRIPTION
vnStat is a console-based network traffic monitor. It keeps a log of 5 minute interval, hourly, daily,
monthly and yearly network traffic for the selected interface(s). However, it isn't a packet sniffer.
The traffic information is read from the proc(5) or sys filesystems depending on availability resulting
in light use of system resources regardless of network traffic rate. That way vnStat can be used even
without root permissions on most systems.
The implementation is divided into two commands. The purpose of the vnstat command is to provide an
interface for querying the traffic information stored in the database whereas the daemon vnstatd(8) is
responsible for data retrieval, caching and storage. Although the daemon process is constantly running as
a service, it is actually spending most of its time sleeping between data updates.
OPTIONS
--add Create database entry for interface specified with -i or --iface option. The daemon can be running
during this operation but will not automatically detect the addition without a restart.
-b, --begin date
Begin the list output with a specific date / time defined by date instead of the begin being
selected based on the number of entries to be shown. If date isn't available in the database then
the closest later date will be used. date supports the following formats: YYYY-MM-DD HH:MM and
YYYY-MM-DD. This option can only be used with --json , --xml and list outputs.
--config file
Use file as configuration file instead of using automatic configuration file search functionality.
-d, --days [limit]
Show traffic statistics on a daily basis for the last days. The length of the list will be limited
to 30 entries unless configured otherwise or unless the optional limit parameter is used. All
entries stored in the database will be shown if limit is set to 0.
--dbdir directory
Use directory as database directory instead of using the directory specified in the configuration
file or the hardcoded default if no configuration file is available.
-D, --debug
Show additional debug output.
-e, --end date
End the list output with a specific date / time defined by date instead of the latest date / time
in the database. If date isn't available in the database then the closest earlier date will be
used. date supports the following formats: YYYY-MM-DD HH:MM and YYYY-MM-DD. This option can only
be used with --json , --xml and list outputs. The top list also requires --begin to be used at the
same time with this option.
-5, --fiveminutes [limit]
Show traffic statistics with a 5 minute resolution for the last hours. The length of the list
will be limited to 24 entries unless configured otherwise or unless the optional limit parameter
is used. All entries stored in the database will be shown if limit is set to 0.
-h, --hours [limit]
Show traffic statistics on a hourly basis. The length of the list will be limited to 24 entries
unless configured otherwise or unless the optional limit parameter is used. All entries store in
the database will be shown if the limit is set to 0.
-hg, --hoursgraph
Show traffic statistics on a hourly basis for the last 24 hours using a bar graph followed by a
table representing the numerical data.
-i, --iface interface
Select one specific interface and apply actions to only it. For queries, it is possible to merge
the information of two or more interfaces using the interface1+interface2+... syntax. All
provided interfaces must be unique and must exist in the database when the merge syntax is used.
--iflist
Show list of currently available interfaces.
--json [mode] [limit]
Show database content for selected interface or all interfaces in json format. All traffic values
in the output are in bytes. An optional mode parameter can be used for limiting the output to only
selected information. Everything is shown by default. Setting mode to 'f' will output only 5
minute resolution entries, 'h' hours, 'd' days, 'm' months, 'y' years and 't' the top days.
Alternatively or in combination with mode an optional limit parameter can be used to limit the
number of entries in the output. The --json option can be used in combination with -l, --live and
-tr options without mode or limit having any effect to the output. The jsonversion field in the
output contains the API version information. It will be changed only when the names or structures
of previously existing content gets changed. In comparison, the vnstatversion field exists only as
extra information.
--limit limit
Set the maximum number of shown entries in list outputs to limit. Usage of --limit overrides the
default list entry limit values and the optional limit parameter given directly for a list query.
All entries stored in the database will be shown if limit is set to 0. --limit can also be used
to control the length of --json and --xml outputs.
-l, --live [mode]
Display current transfer rate for the selected interface in real time until interrupted.
Statistics will be shown after interruption if the runtime was more than 10 seconds. An optional
mode parameter can be used to select between the displaying of packets per second (mode 0) and
transfer counters (mode 1) during execution. --style can also be used to affect the layout of the
output. The output will be in json format if used in combination with --json option.
--locale locale
Use locale instead of using the locale setting specified in the configuration file or the system
default if no configuration file is available.
--longhelp
Show complete options list.
-m, --months [limit]
Show traffic statistics on a monthly basis for the last months. The length of the list will be
limited to 12 entries unless configured otherwise or unless the optional limit parameter is used.
All entries stored in the database will be shown if limit is set to 0.
--oneline [mode]
Show traffic summary for selected interface using one line with a parsable format. The output
contains 15 fields with ; used as field delimiter. The 1st field contains the API version
information of the output that will only be changed in future versions if the field content or
structure changes. The following fields in order 2) interface name, 3) timestamp for today, 4) rx
for today, 5) tx for today, 6) total for today, 7) average traffic rate for today, 8) timestamp
for current month, 9) rx for current month, 10) tx for current month, 11) total for current month,
12) average traffic rate for current month, 13) all time total rx, 14) all time total tx, 15) all
time total traffic. An optional mode parameter can be used to force all fields to output in bytes
without the unit itself shown.
-q, --query
Force database query mode.
--remove
Delete the database entry for the interface specified with -i or --iface and stop monitoring it.
The daemon can be running during this operation and will automatically detect the change.
--rename name
Rename the interface specified with -i or --iface in the database with new name name. The new
name cannot already exist in the database. This operation doesn't cause any data loss. The daemon
should not be running during this operation.
-ru, --rateunit [mode]
Swap the configured rate unit. If rate has been configured to be shown in bytes then rate will be
shown in bits if this option is present. In the same way, if rate has been configured to be shown
in bits then rate will be shown in bytes when this option is present. Alternatively, mode with
either 0 or 1 can be used as parameter for this option in order to select between bytes (0) and
bits (1) regardless of the configuration file setting.
--setalias alias
Set alias as an alias for the selected interface to be shown in queries. The set alias can be
removed by specifying an empty string for alias. The daemon can be running during this operation.
-s, --short
Use short output mode. This mode is also used when more than one interface is available in the
database and no specific interface is selected.
--showconfig
Show current configuration using the same format as the configuration file itself uses.
--style number
Modify the content and style of outputs. Set number to 0 for a narrower output, 1 for enabling bar
column, 2 for same as previous but with average traffic rate visible in summary output and 3 for
enabling average traffic rate in all outputs where it is supported. 4 disables the use of terminal
control characters in -l / --live mode.
-t, --top [limit]
Show all time top traffic days. The length of the list will be limited to 10 entries unless
configured otherwise or unless the optional limit parameter is used. All entries stored in the
database will be shown if limit is set to 0. When used with --begin and optionally with --end, the
list will be generated using the daily data instead of separate top entries. The availability of
daily data defines the boundaries the date specific query can access.
-tr, --traffic [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 specified. The output will be in json format if
used in combination with --json option. However, in that case, the countdown before results isn't
shown.
-v, --version
Show current version.
--xml [mode] [limit]
Show database content for selected interface or all interfaces in xml format. All traffic values
in the output are in bytes. An optional mode parameter can be used for limiting the output to only
selected information. Everything is shown by default. Setting mode to 'f' will output only 5
minute resolution entries, 'h' hours, 'd' days, 'm' months, 'y' years and 't' the top days.
Alternatively or in combination with mode an optional limit parameter can be used to limit the
number of entries in the output. The xmlversion field in the output contains the API version
information. It will be changed only when the names or structures of previously existing content
gets changed. In comparison, the vnstatversion field exists only as extra information.
-y, --years [limit]
Show traffic statistics on a yearly basis for the last years. The list will show all entries by
default unless configured otherwise or unless the optional limit parameter is used. All entries
stored in the database will also be shown if limit is set to 0.
-?, --help
Show a command option summary.
FILES
/var/lib/vnstat/
Default database directory.
/etc/vnstat.conf
Config file that will be used unless $HOME/.vnstatrc exists. See vnstat.conf(5) for more
information.
EXAMPLES
vnstat Display traffic summary for the default interface or multiple interfaces when more than one is
monitored.
vnstat -i eth0+eth1+eth3
Display traffic summary for a merge of interfaces eth0, eth1 and eth3.
vnstat -i eth2 --xml
Output all information about interface eth2 in xml format.
vnstat --json
Output all information of all monitored interfaces in json format.
vnstat -i eth0 --setalias local
Give interface eth0 the alias "local". That information will be later visible as a label when eth0
is queried.
vnstat -i eth2 --remove
Delete database entries for interface eth2 and stop monitoring it.
RESTRICTIONS
Updates need to be executed at least as often as it is possible for the interface to generate enough
traffic to overflow the kernel interface traffic counter. Otherwise, it is possible that some traffic
won't be seen. With 32-bit kernels, the maximum time between two updates depends on how fast the
interface can transfer 4 GiB. 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 usable solution if a shorter
update interval can't be used.
Virtual and aliased interfaces cannot 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.
Using long date output formats may cause misalignment in shown columns if the length of the date exceeds
the fixed size allocation.
AUTHOR
Teemu Toivola <tst at iki dot fi>
SEE ALSO
vnstatd(8), vnstati(1), vnstat.conf(5), proc(5), ifconfig(8), units(7)
version 2.6 JANUARY 2020 VNSTAT(1)