The servers must be configured to allow their performance counters to be collected by the computers running the tests. There are several aspects to this, most are too big and too complex to give full details here, but in outline they are:
The accounts that are chosen to run the tests must have the necessary permissions on relevant computers. When the computers are not all in the same domain then it may be best to create local accounts on each computer, all of these accounts having the same name and the same password. See here for more details.
On each of the servers to be monitored:
The firewall must be opened for the inbound "Performance Logs & Alerts firewall exception".
The username that runs the tests must be added to the "Performance Log Users", "Performance Monitor Users" and the "Event Log Readers" groups.
The services "Performance Logs & Alerts" and "Remote Registry" must be set to autorun.
In the security policies, the groups that can "Log on as batch job" must include the "Performance Log Users" and the "Performance Monitor Users" groups.
The performance counters must be rebuilt by running the command `lodctr /r.
See here and here for more details on setting up the servers.
