Citrix PowerSmart Utility for Presentation Server FAQ
The tool is NOT part of Presentation Server release. We will provide limited forum support only. We would like to encourage our partners to create more feature rich and production ready products using this tool as a reference. This is a new model we are experimenting. And your input will be greatly appreciated.
Which version of Presentation server does the tool support?
This version is tested with CPS4.5 only. However depending on the demand, future version may support CPS 4.0 as well.
Does the tool support Wake On LAN?
We thought about providing a WoL based default for powering up servers because it seems to be widely supported and the concept is simple. However we ran into various problems getting it to work in my test environment. Some problems seem to be network related such as firewall issues etc. But more troubling is that we got inconsistent result when waking up a machine connecting to the same hub. We don’t feel comfortable releasing something that we can’t get working consistently. Thus we didn’t include a default WoL solution in the first release. However users can easily add WoL support by invoking their own WoL based program, scripts.
What server hardware does the tool support?
This release contains sample scripts that work with HP servers with ILO2 support. This is the server hardware we tested. The tool is designed to be flexible and extensible however. With one or two lines of configuration file changes, you can easily configure it to invoke any program or script of your choice to power on/off machines. The sample scripts are standard based to make sure it can be customized to work with a wide range of server hardware. We are also working with our server partners to add additional support. Stay tuned. You are encouraged to use this web site to share your experience, tips and scripts with each other. It’s your opportunity to contribute to the community and do something good for the environment.
Does the tool require Citrix Provisioning Server ( AKA Ardence)?
Although the tool can be configured to work with Provisioning Server, Provisioning Server is not required. Combining the power of Provisioning Server with this tool may create some additional advantages. We are interested in hearing your thoughts.
Does this tool have an Admin UI?
Not yet. It’s currently driven by configuration files. The hope is that once you finish a relatively simple configuration, it will just work! We also would like to keep it simple. The more complex the code is, the more likely it may break. Well to be honest, schedule is a big factor. If we can’t deliver a UI that works well, we may be better off focusing on the basic first. The tool is designed such that a UI can be added without modifying the tool itself. We would like to involve the user community in the design of the admin UI. Maybe someone will create one or multiple admin UIs for the community.
Does the tool support Presentation Server running on virtual machines?
Yes, you can run the tool in a Presentation Server farm which runs on a hypervisor such as Xen or Vmware. However in this release we have not included a default script to power on virtual machines yet. The default power off mechanism still works on virtual machines. You can power off virtual machines and configure the host machine to consume less power automatically when it has less work to do. Some newer servers support this reduced power consumption mode automatically. But if the host is still running, your potential power saving can be limited. That said, having the tool support virtual machines may be important to testing and demo purposes. We didn’t have time to implement and test such scripts in this release. But we do plan to include scripts to in the future to support this scenario. Or it will be even better if users can contribute such scripts.
Can you create a similar tool that will work with generic virtual machines now that Citrix also owns Xen?
Yes, it is an interesting and potentially more powerful solution. For example, we may be able to use live migration to consolidate virtual machines and shut down the idle ones. But we are not there yet. This tool is specifically designed for presentation server. It will take a different tool to work with generic virtual machines. If this project is successful, you may see additional tools you want sooner
How is the power saving calculated?
Right now the calculation is based on a simplified model where we assume the average power consumption when a machine is running is the same. So for example if a machine is shut down 12 hours out of a day 7 days a week, the saving will be 50%.
We are working with HP to get more concrete data. For example, how much is a typical power assumption of a HP server running presentation server? How much is a typical power assumption when there are active user sessions vs no active user sessions. What’s the effect of running servers at a lower power consumption mode?
Will the tool shut down a server when a user session is active?
The tool will not shut down a server when there is an active ICA session on the server. It will however continue to monitor the servers during the “idle management period” and shut it down once the last user logs off.
Will the tool consider a server busy when someone is logged in to the console and there is no ICA session?
No. Otherwise it will prevent an idle CPS server from being shut down if someone unintentionally log into the console and lock the screen without logging out. We think that production CPS servers typically don’t have someone logged into the console. For trouble shooting, administrators may be better off taking the server off the power managed server list first. We will re-evaluate this decision for future releases and we are interested in your feedbacks.
Will the tool consider a server busy when there is a disconnected session?
Yes. Shutting down the server may cause the disconnected user to lose data.
Will disconnected session diminish the saving in production environment?
It depends on the configuration and user behavior. In a typical scenario where published applications are used, if users typically close the application when they are done, users would in effect log off. To disconnect, they would have to go out of their way to use connection centers to do so. A policy can also be set to log off disconnected session after a preset time period.
Please see the PowerSmart User Guide “End a disconnected session after a specified time period” section for more details.
If a sudden shift in work cause a flotilla of works to come in at 3 a.m., will the servers kick on based on the ‘demand’?
No. We understand such a feature will be very desirable. However it is currently not available in this release. Such a feature however is being researched and evaluated for future enhancement.
How is the power on/off operation going to affect server reliability?
Yes, it is a concern. But we’ve heard from our server hardware vendors that today’s hardware has become more reliable. Chances are great they will last until your next hardware refresh cycle. We are still working with HP to get more details on this.
Doesn’t a server consume more power during power on process?
Yes, but not by much. The small increase may very well be offset by a much larger power saving by powering off the servers. We are still working with HP to get more details on this.
What trouble shooting support is included?
By default, some basic information such as when the tool decides to power on/off a server will be logged in the event log of the server running this tool. The servers being shutdown/power off will have the power events logged as usual. The debug tracing is flexible and can be configured to trace only the information you want and to where you want it. Various debugging tools are included to help testing individual components separately. Please see the user guide for more details.
Download Citrix PowerSmart Utility Resources
Download the installation program from here
Download user guide from here