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Network Stress Testing

Stressing an Embedded Network Device

Sometimes a new networked device behaves funny and you need to stress it to try and figure out where the bug is - firmware, hardware, software?

If you feel like you need a big hammer to give the infernal device a good whack, then look no further - get nping, made by the friendly folks over at the nmap project.

Get nping

# yum install nmap

While you are at it, you can also try another hammer called hping:
# yum install hping3

Hammer it

Now you can try hammering the device on its control port with good packets:
$ nping -c 500000 --rate 10000 --tcp --data-length 1500 -g 2000 -p 2000 192.168.111.4
 
and with bad packets:
$ nping -badsum-ip -c 500000 --rate 10000 --tcp --data-length 1500 -g 2000 -p 2000 192.168.111.4

And hopefully, that will cause the device to splutter and squeal and show you where the problem lies.  Even if it doesn't show you anything, hammering it will likely release some stress and make you feel better.

La voila!


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