TRex is an open source, stateful traffic generator fuelled by DPDK. It generates L4-7 traffic based on pre-processing and smart replay of real traffic templates. TRex amplifies both client and server side traffic. Trex can can scale to 200Gb/sec with one UCS, but you can run it in any x86 hardware.
You can build your own VM running Fedora or Ubuntu, but Cisco cooked a OVA and Virtual Box image ready to go here
Cisco DEVNET has a corner for TREX too, check here
It’s time to load some devices, and compare with datasheets
Video here: WP 1 Click Traffic Demo