VNSTAT(1)User Manuals

VNSTAT(1)NAME
vnstat − a console-based network traffic monitor

SYNOPSIS
vnstat [−5bDedhlmqstvy?] [−−95th] [−−add] [−−alert output exit type condition limit unit] [−−begin
date] [−−config file] [−−days [limit]] [−−dbdir directory] [−−dbiflist [mode]] [−−debug] [−−end date][−−fiveminutes [limit]] [−−help] [−hg] [−−hours [limit]] [−−hoursgraph] [−i interface] [−−iface interface] [−−iflist [mode]] [−−json [mode] [limit]] [−−limit limit] [−−live [mode]] [−−locale locale][−−longhelp] [−−months [limit]] [−−oneline [mode]] [−−query [mode]] [−−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]] [interface]

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 onmost systems.
Functionality 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 fordata 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--95thShow 95th percentile output for the ongoing month. This output uses the 5 minute resolution dataof the ongoing month to calculate the 95th percentile traffic rate for received, transmitted and total.
In addition, the minimum, average and maximum traffic rates for received, transmitted and total
are also shown. This output requires the 5MinuteHours configuration option to have a value of atleast 744 for storing all the necessary data, otherwise 100% coverage isn’t possible.

--add

Create database entry for interface specified with −i or −−iface option. The daemon can be running during this operation and will automatically start monitoring the interface without a restart
within SaveInterval minutes if configuration option RescanDatabaseOnSave is enabled. Otherwise the daemon needs to be restarted in order for the added interface to be monitored.

--alert output exit type condition limit unit
Depending on values of given parameters, show alert, use different exit status or a combination ofboth when configured situation is met.
output parameter takes a number from 0 to 3 and controls when, if at all, the command will resultin output. ’0’ never produces output, ’1’ always produces output, ’2’ shows output only when usage estimate exceeds limit and ’3’ shows output only when limit is exceeded.
exit parameter takes a number from 0 to 3 and controls the exit status of the command. ’0’ always
uses exit status 0, ’1’ always uses exit status 1, ’2’ uses exit status 1 if usage estimate exceeds limit
but otherwise exit status 0 and ’3’ uses exit status 1 if limit is exceeded but otherwise exit status 0.
type parameter defines to which time range type usage the limit is compared against. Available options: ’h’, ’hour’, ’hourly’, ’d’, ’day’, ’daily’, ’m’, ’month’, ’monthly’, ’y’, ’year’, ’yearly’, ’p’,
’95’, ’95%’.

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VNSTAT(1)condition parameter defines if limit is compared to received (rx), transmitted (tx), total or estimated usage of these three. Available options: ’rx’, ’tx’, ’total’, ’rx_estimate’, ’tx_estimate’, ’total_estimate’. Estimate options aren’t available for 95th percentile type.
limit is a greater than zero integer without decimals which defines the traffic usage limit using theunit defined with the unit parameter. unit accepts the following options: ’B’, ’KiB’, ’MiB’, ’GiB’,’TiB’, ’PiB’, ’EiB’, ’KB’, ’MB’, ’GB’, ’TB’, ’PB’, ’EB’. For 95th percentile type the following
options are available: ’B/s’, ’KiB/s’, ’MiB/s’, ’GiB/s’, ’TiB/s’, ’PiB/s’, ’EiB/s’, ’kB/s’, ’MB/s’,’GB/s’, ’TB/s’, ’PB/s’, ’EB/s’, ’bit/s’, ’Kibit/s’, ’Mibit/s’, ’Gibit/s’, ’Tibit/s’, ’Pibit/s’, ’Eibit/s’,’kbit/s’, ’Mbit/s’, ’Gbit/s’, ’Tbit/s’, ’Pbit/s’, ’Ebit/s’. Usage must exceed limit in order for thealarm to activate. Exactly the same usage as limit does not raise the alarm.
Estimate calculation isn’t limited to the estimate options in condition parameter but can also be
achieved by using the estimate option in output or exit parameters. Missing or invalid parameters
or parameter combination will result in --alert specific help output being shown.
-b, --begin date
Begin the list output with a specific date / time defined by date instead of the begin being selectedbased 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, YYYYMM-DD and "today". 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. If--config is used multiple times, the configuration settings from files later on the command line will
override configuration settings loaded from earlier files if the settings defined in the files overlap.
-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 fileor the hardcoded default if no configuration file is available.
--dbiflist [mode]
List interfaces currently in the database. If mode is not defined or is set to 0 then the output will
use a one line verbose format. If mode is set to 1 then the output will contain one interface per line
and if mode is set to 2 then only the interface count will be shown as a single number. See also--iflist.
-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. In list outputs the estimate line is replaced with a sum
line with values representing the sums of each column. The sum line is shown only if the output

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VNSTAT(1)consists of more than one data line. This is applicable even if the defined date is the same as thecurrent date. 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 belimited 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 unlessconfigured 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, --hoursgraphShow 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 database queries, it is possible tomerge the information of two or more interfaces using the interface1+interface2+... syntax. Allprovided interfaces must be unique and must exist in the database when the merge syntax is used.
Optionally, depending on the InterfaceMatchMethod configuration setting, interface can be replaced with alias previously set using --setalias. Merge syntax isn’t supported when alias is used.
The -i, --iface option is optional and interface can be used as parameter on the command line forselecting the used interface even without the option being explicitly used.
--iflist [mode]
List currently available interfaces. If mode is not defined or is set to 0 then the output will use aone line verbose format. If mode is set to 1 then the output will contain one interface per line andif mode is set to 2 then only the interface count will be shown as a single number. See also --dbiflist.
--json [mode] [limit]
Show database content for selected interface or all interfaces in json format. All traffic values in
the output are in bytes unless otherwise indicated by the name of the key. An optional mode parameter can be used for limiting the output to only selected information. Everything except the95th percentile output is shown by default. Setting mode to ’s’ will output a summary containing
the last 2 entries of 5 minute, hourly, daily, monthly and yearly resolution data, ’f’ will output only
5 minute resolution entries, ’h’ hours, ’d’ days, ’m’ months, ’y’ years, ’t’ the top days and ’p’ the95th percentile. Alternatively or in combination with mode an optional limit parameter can beused 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 thenames 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 thedefault 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.

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VNSTAT(1)-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 parametercan 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 [mode]
Force database query mode. An optional mode parameter can be used to override the default query
mode. ’a’ results in short summary output being used when there are more than one interface inthe database, otherwise regular summary output is used. ’s’ results in regular summary output being shown for one interface regardless of the number of interfaces in the database. When the optional mode parameter isn’t defined, the configured QueryMode will be used instead.
--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 newname 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 beshown in bits if this option is present. In the same way, if rate has been configured to be shown inbits 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.

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VNSTAT(1)--setalias alias
Set alias as an alias for the selected interface to be shown in queries. The set alias can be removedby 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 forenabling average traffic rate in all outputs where it is supported. 4 disables the use of terminal control characters in -l, --live and -tr, --traffic modes.
-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 beshown 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 theboundaries 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. --style can also be used to affect the layout of the output.
-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 unless otherwise indicated by the name of the key. An optional mode parameter can be used for limiting the output to only selected information. Everything except the95th percentile output is shown by default. Setting mode to ’s’ will output a summary containing
the last 2 entries of 5 minute, hourly, daily, monthly and yearly resolution data, ’f’ will output only
5 minute resolution entries, ’h’ hours, ’d’ days, ’m’ months, ’y’ years, ’t’ the top days and ’p’ the95th percentile. Alternatively or in combination with mode an optional limit parameter can beused 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.

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VNSTAT(1)-?, --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 ismonitored.
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 tooverflow the kernel interface traffic counter. Otherwise, it is possible that some traffic won’t be seen. With
32-bit interface traffic counters, the maximum time between two updates depends on how fast the interface
can transfer 4 GiB. Note that there is no guarantee that a 64-bit kernel has 64-bit interface traffic counters
for all interfaces. Calculated theoretical times are:
10 Mbit:
100 Mbit:1000 Mbit:

54 minutes
5 minutes
30 seconds

Virtual and aliased interfaces cannot be monitored because the kernel doesn’t provide traffic information forthat type of interfaces. Such interfaces are usually named eth0:0, eth0:1, eth0:2 etc. where eth0 is the actualinterface 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>

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VNSTAT(1)SEE ALSO
vnstatd(8), vnstati(1), vnstat.conf(5), proc(5), ifconfig(8), units(7)version 2.12

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