7 Vnstat Command Tips You Need To Learn Now Network Traffic Monitoring Tool

vnstat is a command line network traffic monitoring tool for Linux and Berkeley Software Distribution (BSD). It stores a logs of hourly,daily and monthly network traffic for selected network interfaces. 7 vnstat command tips you need to learn now network traffic monitoring tool.

• It is easy to install and configure.
• It can monitor multiple network interfaces at the same time.
• Vnstat can be used without root permissions.
• It provides the output summery,hourly,daily,weekly,monthly.
• It can generate the output in image/png graphically.
• Low CPU usage regardless of traffic.
• It uses of network interface statistics provided by the kernel as information source.
• Months also can be configured to follow billing period.

Installation of vnstat command

Vnstat command install through yum command (or) we can install manualy by download the

command source package

[root@ArkIT-Srv ~]# wget http://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-9.noarch.rpm
--2017-01-26 19:41:01-- http://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-9.noarch.rpm
Resolving dl.fedoraproject.org (dl.fedoraproject.org)... 209.132.181.27, 209.132.181.24, 209.132.181.23, ...
Connecting to dl.fedoraproject.org (dl.fedoraproject.org)|209.132.181.27|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 14704 (14K) [application/x-rpm]
Saving to: ‘epel-release-7-9.noarch.rpm’

100%[============================================>] 14,704 53.0KB/s in 0.3s

2017-01-26 19:41:17 (53.0 KB/s) - ‘epel-release-7-9.noarch.rpm’ saved [14704/14704]

[root@ArkIT-Srv ~]# rpm -ivh epel-release-7-9.noarch.rpm

[root@Arkit-Serv ~]# yum install -y vnstat
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Warning: RPMDB altered outside of yum.
 Installing : vnstat-1.15-2.el7.x86_64 1/1
 Verifying : vnstat-1.15-2.el7.x86_64 1/1

Installed:
 vnstat.x86_64 0:1.15-2.el7

Complete!

(or)

[root@ArkIT-Srv ~]# wget http://humdi.net/vnstat/vnstat-1.13.tar.gz
--2017-01-26 18:46:03-- http://humdi.net/vnstat/vnstat-1.13.tar.gz
Resolving humdi.net (humdi.net)... 213.168.251.41, 2a01:7e00::f03c:91ff:fe37:3421
Connecting to humdi.net (humdi.net)|213.168.251.41|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 101568 (99K) [application/x-gzip]
Saving to: ‘vnstat-1.13.tar.gz’

100%[================================================>] 101,568 326KB/s in 0.3s

2017-01-26 18:46:04 (326 KB/s) - ‘vnstat-1.13.tar.gz’ saved [101568/101568]

[root@ArkIT-Srv ~]# tar -xvf vnstat-1.13.tar.gz

[root@Arkit-Serv ~]# make install

vnstat commnd configuration

If you want find the network interfaces on your system use below command

[root@ArkIT-Srv ~]# vnstat --iflist
Available interfaces: eno16777736 (1000 Mbit) lo

Edit below file for set the interface

[root@Arkit-Serv ~]# vi /etc/sysconfig/vnstat

VNSTAT_OPTIONS="-u -i eth0" <== default interface.

Replace default interface to your system interface.

Enable the vnstat service in RHEL 5 or RHEL 6

[root@Arkit-Serv ~]# chkconfig vnstat on

Start the vnstat service in RHEL 7 / Centos 7

[root@Arkit-Serv ~]# systemctl stop vnstat.service

[root@Arkit-Serv ~]# systemctl restart vnstat.service

[root@ArkIT-Srv ~]# systemctl start vnstat.service
[root@ArkIT-Srv ~]# systemctl status vnstat.service
vnstat.service - vnStat network traffic monitor
 Loaded: loaded (/usr/lib/systemd/system/vnstat.service; disabled)
 Active: active (running) since Thu 2017-01-26 19:49:21 IST; 13s ago
 Docs: man:vnstatd(1)
 man:vnstat(1)
 man:vnstat.conf(5)
 Main PID: 4303 (vnstatd)
 CGroup: /system.slice/vnstat.service
 └─4303 /usr/sbin/vnstatd -n

Create the new database for network traffic monitoring

Now need to create a new database for network traffic monitoring. Force a database update for interface eno16777736 or create the database if it doesn’t exist. This is usually the first command used after a fresh install if the daemon isn’t used.

[root@ArkIT-Srv ~]# vnstat -u -i eno16777736

Vnstat Command options

[root@Arkit-Serv ~]# vnstat --help

vnStat 1.16 by Teemu Toivola

• -q, –query query database
• -h, –hours show hours
• -d, –days show days
• -m, –months show months
• -w, –weeks show weeks
• -t, –top10 show top10
• -s, –short use short output
• -u, –update update database
• -i, –select interface (default: eth0)
• -?, –help short help
• -v, –version show version
• -tr, –traffic calculate traffic
• -ru, –rateunit swap configured rate unit
• -l, –live show transfer rate in real time

we can see also complete options list with below command

[root@Arkit-Serv ~]# man vnstat

(or)

[root@Arkit-Serv ~]# vnstat --longhelp

[root@Arkit-Serv ~]# vnstat

Check vnstat version

[root@Arkit-Serv ~]# vnstat -v

Statistics of hourly, daily,monthly 

We can simply fetch the using option -d = Daily, -h Hourly, -m = Monthly

[root@ArkIT-Srv ~]# vnstat -d

 eno16777736 / daily

 day rx | tx | total | avg. rate
 ------------------------+-------------+-------------+---------------
 01/26/2017 7 KiB | 6 KiB | 13 KiB | 0.00 kbit/s
 ------------------------+-------------+-------------+---------------
 estimated -- | -- | -- |
[root@Arkit-Serv ~]# vnstat -h

[root@Arkit-Serv ~]# vnstat -m
eno16777736 / monthly

 month rx | tx | total | avg. rate
 ------------------------+-------------+-------------+---------------
 Jan '17 7 KiB | 6 KiB | 13 KiB | 0.00 kbit/s
 ------------------------+-------------+-------------+---------------
 estimated -- | -- | -- |

Live monitoring

Monitoring Live data is so simply using below command, to come back that interface we have to press CTRL+C key.

[root@ArkIT-Srv ~]# vnstat --live -i eno16777736
Monitoring eno16777736... (press CTRL-C to stop)

 rx: 1 kbit/s 1 p/s tx: 1 kbit/s 0 p/s^C


 eno16777736 / traffic statistics

 rx | tx
--------------------------------------+------------------
 bytes 8 KiB | 18 KiB
--------------------------------------+------------------
 max 1 kbit/s | 1 kbit/s
 average 0.36 kbit/s | 0.80 kbit/s
 min 0 kbit/s | 1 kbit/s
--------------------------------------+------------------
 packets 133 | 99
--------------------------------------+------------------
 max 2 p/s | 1 p/s
 average 0 p/s | 0 p/s
 min 0 p/s | 0 p/s
--------------------------------------+------------------
 time 2.97 minutes

Top 10 statistics

[root@Arkit-Serv ~]# vnstat -t
eno16777736 / top 10

 # day rx | tx | total | avg. rate
 -----------------------------+-------------+-------------+---------------
 no data available
 -----------------------------+-------------+-------------+---------------

[root@ArkIT-Srv ~]# vnstat -tr -i eno16777736
8 packets sampled in 5 seconds
Traffic average for eno16777736

 rx 0.38 kbit/s 0 packets/s
 tx 0.79 kbit/s 0 packets/s

Graphical output

Daily display of stats

[root@Arkit-Serv ~]# vnstati -d -i eth0 -o ~/daily.png

here “-o” option to specify where the output file will be stored.

Querying Database vnstat command

Database querying using vnstat command

[root@ArkIT-Srv ~]# vnstat -q
Database updated: Thu Jan 26 19:50:52 2017

eno16777736 since 01/26/2017

rx: 7 KiB tx: 6 KiB total: 13 KiB

monthly
 rx | tx | total | avg. rate
 ------------------------+-------------+-------------+---------------
 Jan '17 7 KiB | 6 KiB | 13 KiB | 0.00 kbit/s
 ------------------------+-------------+-------------+---------------
 estimated -- | -- | -- |

daily
 rx | tx | total | avg. rate
 ------------------------+-------------+-------------+---------------
 today 7 KiB | 6 KiB | 13 KiB | 0.00 kbit/s
 ------------------------+-------------+-------------+---------------
 estimated -- | -- | -- |

Monitor Multiple Interfaces

Display traffic summary for a merge of interfaces eth0, eth1 and eth3.

[root@ArkIT-Srv ~]# vnstat -i eth0+eth1+eth3

Output all information about interface eno16777736 in xml format.

[root@ArkIT-Srv ~]# vnstat -i eno16777736 --xml
<vnstat version="1.15" xmlversion="1">
 <interface id="eno16777736">
 <id>eno16777736</id>
 <nick>eno16777736</nick>
 <created><date><year>2017</year><month>01</month><day>26</day></date></created>
 <updated><date><year>2017</year><month>01</month><day>26</day></date><time><hour>20</hour><minute>03</minute></time></updated>
 <traffic>
 <total><rx>51</rx><tx>56</tx></total>
 <days>
 <day id="0"><date><year>2017</year><month>01</month><day>26</day></date><rx>51</rx><tx>56</tx></day>
 </days>
 <months>
 <month id="0"><date><year>2017</year><month>01</month></date><rx>51</rx><tx>56</tx></month>
 </months>
 <tops>
 </tops>
 <hours>
 <hour id="19"><date><year>2017</year><month>01</month><day>26</day></date><rx>7</rx><tx>6</tx></hour>
 <hour id="20"><date><year>2017</year><month>01</month><day>26</day></date><rx>44</rx><tx>50</tx></hour>
 </hours>
 </traffic>
 </interface>
</vnstat>

Output all information of all monitored interfaces in json format.

[root@ArkIT-Srv ~]# vnstat --json
{"vnstatversion":"1.15","jsonversion":"1","interfaces":[{"id":"eno16777736","nick":"eno16777736","created":{"date":{"year":2017,"month":1,"day":26}},"updated":{"date":{"year":2017,"month":1,"day":26},"time":{"hour":20,"minutes":3}},"traffic":{"total":{"rx":51,"tx":56},"days":[{"id":0,"date":{"year":2017,"month":1,"day":26},"rx":51,"tx":56}],"months":[{"id":0,"date":{"year":2017,"month":1},"rx":51,"tx":56}],"tops":[],"hours":[{"id":19,"date":{"year":2017,"month":1,"day":26},"rx":7,"tx":6},{"id":20,"date":{"year":2017,"month":1,"day":26},"rx":44,"tx":50}]}}]}

Give interface eno16777736 the nickname “local”. That information will be later later visible as a label when eno16777736 is queried. The database will also be updated
when this command is executed or created if the database doesn’t exist.

[root@ArkIT-Srv ~]# vnstat -u -i eno16777736 --nick local
[root@ArkIT-Srv ~]# vnstat -q
Database updated: Thu Jan 26 20:26:17 2017

local (eno16777736) since 01/26/2017

rx: 136 KiB tx: 171 KiB total: 307 KiB

monthly
 rx | tx | total | avg. rate
 ------------------------+-------------+-------------+---------------
 Jan '17 136 KiB | 171 KiB | 307 KiB | 0.00 kbit/s
 ------------------------+-------------+-------------+---------------
 estimated -- | -- | -- |

daily
 rx | tx | total | avg. rate
 ------------------------+-------------+-------------+---------------
 today 136 KiB | 171 KiB | 307 KiB | 0.03 kbit/s
 ------------------------+-------------+-------------+---------------
 estimated -- | -- | -- |

Delete Particular Interface Database

[root@ArkITServ ~]vnstat -i eth2 --delete

Delete database of interface eth2 and stop monitoring it.

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