ANTSLOAD 17 - Performance counters across domains
- Date: 9 Nov 2006
- Products affected: ANTS Load (all)
ANTS Load, in addition to showing HTTP request statistics, can also correlate a Windows Server's performance counters into the test. Although ANTS Load can test any website on any platform, performance counter collection is specific to the Windows platform. Performance counters are collected using the NetBios protocol, which unlike HTTP and TCP, is not routable across disparate networks. This can be worked around, however, using virtual private networks (VPNs), which create a 'tunnel' that makes a computer on a different network virtually part of the Windows Server's local network.
Connecting a VPN
There are many types of VPN: Windows Routing and Remote Access Service, and proprietary VPNs produced by vendors such as Cisco. RRAS can allow the user to log on with Windows credentials. Some third-party VPNs can integrate with Windows, and others cannot. In either case, the VPN allows you to be able to connect to a remote network, even if the addresses are private, such as the 172.16.x.x, 10.x.x.x, and 192.168.x.x network addresses.
Windows Performance Counters
Performance counter access has two prerequisites. First, that the computer is connected to the same network as the server, which can be achieved through the connection of a VPN. The second prerequisite is access to the performance counters. In the case of Windows Server 2003, there is a 'special group' called Performance Monitor Users, members of which are allowed access to the builtin performance counters. In some cases, such as SQL Server, special folder access is required. If the user is in the local server's Administrators group, there is no doubt about access to all performance objects and counters.
Once the computer is connected using a VPN and a user account with access to performance counters is logged in, ANTS Load can be used to perform a test including the server's performance counters.
Logging in using the VPN
If the VPN is Windows security-aware, the user should connect to the VPN using an account with the appropriate rights to the server's performance counters. If the VPN is not Windows security-aware, there is a workaround: simply establish a connection to the remote server using network sharing after connecting the third-party VPN software. To do this, click the start bar, then Run, and enter the IP address of the server:
This will force a login dialog in which you can enter an administrator password for the server.\\10.1.1.1
Adding the performance counters to ANTS Load
Once you have successfully logged in to the server, you can add the performance counters to ANTS Load. Assuming you have already set up an ANTS Load project, you can click the 'Edit Load' button and then the counters tab.
Click the * button to add the counters. In the computer text box, enter the IP address for the server that you had connected network sharing to previously (without the '\\') and press the TAB key. The performance objects from the server should then be transferred to ANTS Load (this may take a few seconds)
Next, select the performance object that interests you, then the counters, then the instance, then Add. Continue adding objects, counters and instances that you would like to see in the ANTS Load test results. When you are finished, click close.
You may now either run the ANTS Load test, or save it to an .ANTS file. Please remember that if you save a project (.ants) file and want to re-use it later, you must first connect to the server using network sharing again by using Start->Run (\\IP.Address) before running the saved test.
If you have a VPN connection available to the web server that you are testing, this should allow you to include Windows performance counters in your load test, even if your computer is not on the web server's local network. Once the VPN is connected and the remote computer becomes part of the same network as the web server and the appropriate login credentials have been established with the web server, ANTS Load is capable of collecting performance object data and integrating it into the load test results.