This script was modified from the original version made by Julien Touche 
with the intention to support iperf3, it monitors the speed between 
network links using the iperf3 command, which is an active tool for
measurements of the maximum achievable bandwidth on IP networks. 

check_iperf3.pl allows you to test both, TCP and UDP protocols, also, 
PERFORMANCE DATA is returned back to Nagios.

Keep in mind that iper3 is not compatible with iperf2, so
this script will run succesfully with an <iperf3_target_server> only.



INSTALL
-------

 $ sudo install --mode=755 check_iperf3.pl /usr/local/bin
 $ sudo cpan -i JSON
 
 
 
NRPE setup
----------

in /etc/nagios/nrpe_local.cfg add the following lines (run check_iperf3.pl
without parameters for usage instructions):

 # get link_max_capacity, critical under 50, warning under 60
 command[chk_iperf3_tcp]=/usr/local/bin/check_iperf3.pl <target_iperf3_server> 50 60
 
 # udp 300Mbps/sec test 
 command[chk_iperf3_udp]=/usr/local/bin/check_iperf3.pl <target_iperf3_server> 150 200 300M
 ...
 # udp 3Mbps/sec wifi test 
 command[chk_iperf3_udp_wifi_6Mbps]=/usr/local/bin/check_iperf3.pl <target_iperf3_server> 4:8 5:7 6M
 
 

NAGIOS server
-------------

In Nagios Server you must create a new check_nrpe command wich will call
the machine running nrpe_server + check_iperf3.pl(wich wraps iperf3 client).

By default <check_iperf3.pl> run a 30 seconds test, so it's necessary to
define a custom "timeout". (standard check_nrpe defaults to 10 seconds).

 define command {
   command_name   check_nrpe_iperf
   command_line   $USER1$/check_nrpe -H $HOSTADDRESS$ -t 60 -c $ARG1$
 }
 
 
 
TCP sample output
-----------------

	$ check_iperf3.pl 10.0.1.10 5 10   
	OK: iperf returns 11.01MB |Bandwidth=11.01MB
	INFO: 
	************************************************************
	  Iperf Version         : iperf 3.0.11
	  Remote Host:Port      : 10.0.1.10:5201
	  Protocol              : TCP
	  TCP MTU               : 1340
	  Streams               : 1
	  Test duration (sec)   : 30
	  Speed (bytes/sec)     : 11.01 MB/sec
	  Speed (bits/sec)      : 88.11 Mb/sec
	  Block Size            : 131072
	  Bytes transmitted     : 330415860
	************************************************************
	DEBUG CMD: $ /usr/bin/iperf3 -J -c 10.0.1.10  -t 30 



UDP sample output
-----------------

	$ check_iperf3.pl 10.0.1.10 5 10 120M
	OK: iperf returns 14.71MB |Bandwidth=14.71MB;;;; Jitter=60.0712ms;;;; Lost_packets_ratio=98.87%;;;;
	INFO: 
	************************************************************
	  Iperf Version         : iperf 3.0.11
	  Remote Host:Port      : 10.0.1.10:5201
	  Protocol              : UDP
	  Streams               : 1
	  Test duration (sec)   : 5
	  Speed (bytes/sec)     : 14.71 MB/sec
	  Speed (bits/sec)      : 117.65 Mb/sec
	  Block Size            : 8192
	  Packets transmitted   : 8795
	  Bytes transmitted     : 73531392
	  Jitter (ms)           : 60.0712
	  Lost Packets          : 8696
	  Lost/Total Ratio (%)  : 8696/8795 (98.87)
	************************************************************
	DEBUG CMD: $ /usr/bin/iperf3 -J -c 10.0.1.10 -u -b 120M -t 5 

	Wow!, see the packet lost ratio!