We have a customer still using ESXi 5.5. Plans are in place to upgrade in the future, but this is several months away. The customer has 2 hosts running on identical Lenovo hardware. I don't have the exact specs in front of me at the moment, but the hosts are adequately resourced. It appears there are network performance issues with one of the hosts. These came to light when attempting to implement a new backup solution that utilizes the management interfaces to perform backups. Backup performance on one of the hosts is fine, but poor on the other. I want to do some testing to try to find out the cause of this. I came across an unsupported way to use iPerf to test performance on ESXi 5.5 (iPerf is included with ESXi 6.0 and above). Short of using iPerf, are there any built-in utilities in ESXi 5.5 to test performance between a host and another device?