User Manual

TRex 14 / 113
3.3 TRex on ESXi
General recommendation: For best performance, run TRex on "bare metal" hardware, without any type of VM. Bandwidth on a
VM may be limited, and IPv6 may not be fully supported.
In special cases, it may be reasonable or advantageous to run TRex on VM:
• If you already have VM installed, and do not require high performance.
• Virtual NICs can be used to bridge between TRex and NICs not supported by TRex.
3.3.1 Configuring ESXi for running TRex
1. Click the host machine, then select Configuration → Networking.
a. One of the NICs must be connected to the main vSwitch network for an "outside" connection for the TRex client and
ssh:
b. Other NICs that are used for TRex traffic must be in a separate vSwitch:
2. Right-click the guest machine → Edit settings → Ensure the NICs are set to their networks:
Note
Before version 2.10, the following command did not function correctly:
sudo ./t-rex-64 -f cap2/dns.yaml --lm 1 --lo -l 1000 -d 100
The vSwitch did not route packets correctly. This issue was resolved in version 2.10 when TRex started to support ARP.
3.3.2 Configuring Pass-through
Pass-through enables direct use of host machine NICs from within the VM. Pass-through access is generally limited only by the
NIC/hardware itself, but there may be occasional spikes in latency (~10ms). Passthrough settings cannot be saved to OVA.
1. Click the host machine. Enter Configuration → Advanced settings → Edit.