network stress test tools?

[dan__wright]

Hi,

i need to find some tools to allow me to stress test / flood a local subnet but not much having much luck, i was hoping someone on here may have some recommendations (preferably free but not an issue its paid for)

we had an issue last week where an interface in a device on our network developed a fault and flooded the network with broadcasts. The outcome of this is we need to put something in place to sto this happening again, i have the solution sorted but we need to do testing to confirm / prove it does what we say it will so need to find a way to flood a vlan.

first thought was create a loop and turn off bpdus on the looped ports to allow broadcast storm but the problem is we are giving one of our directors a list of possible things to do to any of the switches and we have to determine where it is etc to prove it isolated the issue so unless i change it on far too many switches its not going to work, it would be easier if i could give them a laptop with some software on it that would flood that segment.

any suggestions?

this is on our internal networks and approved by management / exec, not some script kiddie wanting to DoS someone.

 

[mattjw916]

So if I understand what you want to do, i.e. create a broadcast storm, it's actually pretty easy to do. Put two ports in the same vlan and disable spanning-tree for that vlan. Then either crossover cable the ports together or use a hub/switch between them that isn't running spanning-tree. Generate some ARPs on that vlan and you get an instant broadcast storm.

If you want to prevent the condition from occurring then enable bpduguard globally on the switch which will errdisable the port if it receives a BPDU where it shouldn't be, i.e on a host port.

 

[mattjw916]

Also, if you want to straight up limit broadcast traffic you can look into using the "storm-control" feature.

I am assuming you are talking about IOS based switches but most vendors have an equivalent.

 

[keenan]

If you want to inject artificial traffic instead of inducing an actual storm, I've used Bit-Twist to do similar things in the past, but not in quite a while. Worth a look, anyway.

 

[SpaceHonkey]

You may want to look into hping...