PowerMAN Frequently Asked Questions (FAQ)
PowerMAN Power Manager is a powerful tool but shouldn't take very long to get to grips with.
The following sections answer some of the most common questions:
What is PowerMAN Power Manager?
Which platforms support PowerMAN?
How does the reporting work? Will the reporting slow down our network? Do I have to use it?
How do you configure PowerMAN?
What is computer insomnia?
How long does PowerMAN take to deploy?
We need to wake computers to install updates or perform AV scans. How can we do this?
How does PowerMAN work?
We want to save energy but we have important tasks that must not be interrupted. How can we do this?
We frequently re-install our PCs. Will the reporting continue to work?
Windows® Vista/7 can configure some power features using Group Policy. Why do I need PowerMAN?
Is there any limit on trial/evaluation deployment?
What happens when the evaluation PowerMAN product key expires?
Can PowerMAN exclude specific computers from power management in the same OU?
What is the policy enforcement feature? How does it work?
How do I investigate power management problems? What is the Power Management Event Log?
How scalable is the PowerMAN solution?
How do I implement PowerMAN? How can I maximize energy savings?
Why do I need PowerMAN? There are some power management settings in the computer BIOS
Does PowerMAN use Wake-On-LAN (WoL)? Will WoL work on my network?
What is the relationship between PowerMAN and PowerMON?
What is the difference between PowerMAN and Group Policy Preferences?
Can PowerMAN be deployed in a pre-built software image or 'Ghost'-style deployment?
How can I do a small PowerMAN deployment without Group Policy or similar?
We regularly re-image our computers or dual-boot them. How many licenses do we need?
Does PowerMAN save my documents before saving energy?
Will power management cause power surges or blow fuses?
What is PowerMAN Power Manager?
PowerMAN Power Manager is a client-side service that is installed on each computer in your organisation.
The software performs two key functions:
- Configure PowerMAN applies your chosen power policy and schedule. Different policies may be applied to different users, groups and computers. If necessary PowerMAN can optionally enforce the policy to prevent unauthorised changes and avoid computer insomnia.
- Report PowerMAN can optionally monitor the usage pattern of each PC and report to either Data Synergy's hosted servers or your own server. This information can be used to monitor your policy and measure your savings.
Which platforms support PowerMAN?
PowerMAN supports the following platforms:
- PowerMAN Client – Windows XP Professional, Windows Vista and Windows 7
- Enterprise Server – Windows Server 2003 and 2008
NB: We do not recommend that active power management is applied to production servers. However, PowerMAN can be used
on these operating systems when they are used as workstations.
How does the reporting work? Will the reporting slow down our network? Do I have to use it?
PowerMAN includes a powerful reporting engine. Anonymous power related data is collected and uploaded every night
to either Data Synergy's hosted servers or your own Enterprise Server. You can use this information to monitor
application of your power policy, spot problems and calculate savings.
The PowerMAN reporting process system is designed to have no impact on network performance
or other infrastructure. Approximately 0.5KB of data is collected each day for each
PC and typically the client software will only transfer this to the logging server
once per day. The upload occurs at a random time and not as soon as the PC is
turned on. An organisation with 1000 computers will produce 500KB of data per day.
This is equivalent to less than half of one 3.5” floppy disk. The reporting system is
highly recommended but
optional.
PowerMAN uploads the report information after the end of each day. Typically, this happens between
00:00 and 03:00 the following day or the next time the computer is powered up. The uploaded information
normally appears on the live reports within a few minutes. If you install the software today you
can start to look at the reported statistics tomorrow.
If you need to know more information about the anonymous information collected please
contact
Technical Support.
How do you configure PowerMAN?
PowerMAN is configured using Windows® Group Policy or direct registry settings. The settings are easy to understand
and are fully documented in the Administrator Guide.
What is computer insomnia?
You can use PowerMAN to create policies that define what should happen when the computer is idle
for an extended period. Typically these are used to logout, sleep, hibernate or shutdown the computer.
Some applications can prevent your computer from becoming idle and keep the computer awake. There are some
legitimate reasons for this such as playing a DVD/Presentation, performing a virus scan or a system update.
However, sometimes rogue applications, user configuration, or even Windows itself can keep the computer awake.
PowerMAN includes a
powerful enforcement feature that can independently monitor the system
and ensure that the policy applies as expected.
How long does PowerMAN take to deploy?
A typical PowerMAN deployment can be divided into three stages. Each stage does not take very long but the product will work best if you pause between phases to monitor and assess the results:
- Deploy in monitoring mode. This is the most important stage and will allow you to understand the current situation and formulate a policy that can improve it
- Apply some initial power configuration
- Wait and re-monitor to see the effect of your configuration. Consult the users and repeat as required
Typically we would recommend that the initial monitoring phase run for
at least two weeks before you consider
applying any active power management. PowerMAN should take less than an hour to deploy in a standard Group Policy based environment.
We would recommend that you allow each power configuration several days (longer is better) operation before considering changing it.
We need to wake computers to install updates or perform AV scans. How can we do this?
PowerMAN includes a scheduled wake policy and this is supported on most modern hardware. You can use the
SLEEPCHECK command
to confirm if your hardware is compatible with this. This can be configured to wake systems to perform regular tasks such
as system updates or AV scans.
Microsoft Windows ® only permit wake from the Sleep and Hibernate states. Some motherboards extend this
by supporting full power-on (from the shutdown state). Unfortunately, because each system implements the feature differently PowerMAN
cannot be used to configure this feature.
How does PowerMAN work?
Power Manager installs a client service called PowerMAN.exe on each computer. The service spends the vast majority of the time idle and therefore does not result in any measurable loss of system performance. Periodically (every 5-10 minutes) the service wakes and checks the current status of the computer. This process only takes a fraction of a second.
During each cycle the service performs the following:
- Determines if the system has recently been accessed by a user
- Checks for the managed power scheme (‘Managed policy for [username]’)
- Creates the power scheme if necessary
- Updates the scheme settings according to the administrator configuration
PowerMAN is fully capable of configuring the power management settings for users who are not permitted, themselves, to perform this action. Unlike most other solutions for power management this is achieved without lowering any of the security safeguards build into the operating system. In addition PowerMAN provides finer control not normally available including:
- Default user power policy
- Separate policy for the logon prompt screen (when no user is logged on)
- Separate policy per user (if required)
- Scheduled wake
- Scheduled shutdown
- Full management reporting
- User override (for permitted users)
- Protection against shutdown/sleep when specific programs are running or files present
NB: PowerMAN is active less than 0.01% the time. Therefore the user is never aware of PowerMAN performing its task.
We want to save energy but we have important tasks that must not be interrupted. How can we do this?
Power Manager allows a list of
Protected Programs and
Protected Files to be defined. When such a program is running or
file exists the Power Manager will automatically prevent the system from entering a reduced power state.
We frequently re-install our PCs. Will the reporting continue to work?
Power Manager uses a combination of the site identity and the network card hardware (MAC) address to form a unique computer identity.
This identity is persistent and will be regenerated if the computer is reinstalled. Once created the identity will be retained if the computer is renamed or the network card subsequently replaced.
If the computer is only infrequently re-installed it is probably acceptable for the most frequent power usage information to be lost during this process. However, if the computer is frequently re-installed you can use the Log Backup setting to store the power usage information in a backup file. You are responsible for preserving this file and restoring it as part of you re-installation process.
Windows® Vista/7 can configure some power features using Group Policy. Why do I need PowerMAN?
Windows® Vista and later include basic Group Policy support for power management. However, as many customers
have found, the features offered can be inflexible to real-life demands and lead to compromises in power
management efficiency. PowerMAN offers many features beyond those present in Windows to ensure you maximise the savings.
You can read more about this:
Is there any limit on trial/evaluation deployment?
We are confident PowerMAN will be easy for you to deploy and will be quickly saving
you money. To demonstrate this we offer a standard 30 day evaluation of the full
product. The trial allows you to deploy PowerMAN to
any number of computers and
includes access the full web-based management reporting. If you need longer to evaluate
the product are happy to extend the period if required.
What happens when the evaluation PowerMAN product key expires?
PowerMAN evaluation product keys are designed to expire. When this happens PowerMAN
stops applying new power settings and stops reporting usage information to the reporting
server (if used). The PowerMAN service continues to run and internally cache usage
information. In a normal configuration the log data is retained for 28 days.
If a new product key is applied PowerMAN resumes normal operation following the next
system reboot.
There is
no user pop-up when the product key expires and the process is
transparent to the user. PowerMAN continues to report in the event log.
Can PowerMAN exclude specific computers from power management in the same OU?
Normally it is possible to apply the same power management configuration to each
computer within an organisational unit (OU) and use a separate OU for each logical
power policy. However, sometimes this may not be desirable or it may not be practical
to re-arrange the OUs to match the required power scheme. In this scenario the
Protected Files feature may be used to exclude specific computers.
To use this procedure proceed as follows:
-
Create an empty text file which matches the computer name. One way to do
this is to use a computer start-up script to execute the following batch file:
echo %computername% > c:\%computername%.txt
- Use the Protected Files feature to exclude the c:\%computername%.txt file.
For instance the following settings would exclude three computers:
c:\CriticalPC.txt
c:\OfficePC.txt
c:\FaxServer.txt
The following Microsoft document provides further information on computer start-up scripts:
Assign computer startup scripts
What is the policy enforcement feature? How does it work?
Windows uses an idle countdown timer to track the last significant system activity.
When this timer reaches zero the computer normally enters a low-power state (suspend).
Activity such as keyboard/mouse or CPU usage can reset this timer and postpone the
low-power state.
The Windows timer can also be inhibited or reset by applications. Applications
legitimately do this when performing a critical task (such as an update) or when
it would be inconvenient to the user for the system to enter a different power state.
For instance, the idle timer is disabled when Microsoft PowerPoint is performing a
slideshow.
In some circumstances applications may make excessive use of this feature. This is
sometimes known as PC "insomnia" and results in the selected power management policy
not performing as expected. This will reduce system energy efficiency and increase
operating costs. Depending upon the installed applications this phenomenon may almost
never happen or may be a constant problem. PowerMAN includes a powerful policy
enforcement feature that can be used to overcome this undesirable behaviour.
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The PowerMAN Reporting system marks periods spent in this "forced awake"
state with an exclamation mark (!) symbol. This will result in increased
energy consumption if it occurs during otherwise inactive (red) periods.
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There are several signs that policy enforcement may be required:
- Computer power settings often fail to behave as configured
- Power Management event log reports "The computer is being prevented from entering the idle state by an unknown program"
- The historic report for a computer include significant periods marked ‘forced awake’ – indicated with the exclamation mark (!) symbol character
The PowerMAN Policy Enforcement feature allows you to configure a further
timeout in
addition to the standard timeout setting. When this time has expired
PowerMAN will force the configured power action to occur. This works alongside
the Protected Programs/Files feature and will not enforce a power action whilst
protection is active.
How do I investigate power management problems? What is the Power Management Event Log?
PowerMAN incorporates a powerful power management event logging feature.
This can be accessed with the standard Windows event viewer tool Eventvwr.exe.
The event log combines relevant power related events together with PowerMAN
activity in chronological order. This information can be extremely useful
when investigating power management problems or fine tuning settings. There
is a summary of the most commonly logged events in the Administrator guide.
PowerMAN can be configured to log additional information using the appropriate
option under Advanced/Event Logging. The PowerMAN service must be restarted
or the computer rebooted for this change to become effective.
In Windows Vista / Windows 7 the Power Management event log is located under Applications
and Services Logs.
How scalable is the PowerMAN solution?
PowerMAN is very lightweight and scales very well. The client software
(power policy implementation) is configured using standard registry based
settings or Windows Group Policy. This does not normally require any additional
server resources and will scale to the largest Windows based networks with ease.
The PowerMAN reporting (server) software is only used for reporting and
can handle > 50,000 computers on a single server. PowerMAN has minimal
bandwidth requirements. Typically, less than 500 bytes of network traffic is
generated per client PC per day and around 1MB of data is logged per PC
per year.
How do I implement PowerMAN? How can I maximize energy savings?
The
most effective PowerMAN deployments use an initial passive monitoring
phase to fully understand the existing usage profile. This passive process
is transparent to users and allows you to collect information that can then
be used to better the specific strategy you use to reduce PC energy waste.
After you have implemented an energy reduction initiative it can be very
useful to refer back to the data previously logged to measure progress and
identify areas for possible further improvement.
Why do I need PowerMAN? There are some power management settings in the computer BIOS
Modern, Windows NT-based, operating systems implement power management using the ACPI standard.
This has replaced the older APM system. When using Windows 2000 or later the BIOS power management
settings are not used and will have no effect. Power management on such computers is configured
directly in Windows. PowerMAN provides a simple method to centralise this process.
Does PowerMAN use Wake-On-LAN (WoL)? Will WoL work on my network?
PowerMAN uses two different systems for PC wake-up.
The scheduled wake-up feature uses the timer built-in to most modern computers.
This more reliable than WoL techniques and does not require any network communication.
You can test this feature on a PC by using the SLEEPCHECK or HIBERCHECK commands.
The scheduled wake feature is not suitable for ad-hoc wake because the timer must be configured
before the PC enters the low-power state.
The PowerMAN server system also allows you to perform ad-hoc system wake-up using Wake-On-LAN (WoL).
This can be accomplished by clicking the link provided on the server reports
or by manually forming the required wake URL. This feature requires the Data Synergy
wake proxy software. This is available upon request from Data Synergy Technical Support.
To use a WoL based technique some computers will need this feature to be enabled.
This configuration is usually accomplished in two phases:
- Wake-on-LAN must be enabled in the BIOS. The Data Synergy DMCMOS32 tool may be used to automate this process
- The network card must support WoL and this must be enabled in Windows Device Manager
Wake-On-LAN is not a mature technology and can
fail for a number of reasons which are beyond PowerMAN’s control
The most common issues are:
- WoL uses broadcast network packets. These are not normally routable and therefore only work within the local sub-net. This why the Wake Proxy is necessary. It may, in some cases, also be possible to re-configure your router to forward WoL packets
- A typical WoL implementation does not include any security. It is possible to wake an arbitrary PC on the local sub-net. This should not normally be a significant security concern
- WoL must be enabled in the system BIOS and usually in Windows Device Manager. There is sometimes a degree of trial and error required to get WoL working
Data Synergy provides the free WoLMAN tool to aide WoL debugging. This is available
here.
What is the relationship between PowerMAN and PowerMON?
Data Synergy distributes the PowerMAN client software in two forms. The full software
product is known as PowerMAN. This allows power management policies to be applied and
power usage information to be monitored. PowerMON is a limited feature version of the
same software that is used only for power monitoring. The same executable is used for
both products. The term PowerMAN is generally used in the documentation. The supplied
license key and ADM file are different.
What is the difference between PowerMAN and Group Policy Preferences?
Group Policy Preferences (GPP) allow you to assign initial power policy settings to users. GPP has number
of important limitations:
- The settings are only preferences. The users can change them
- GPP does not include policy enforcement or solve for PC 'Insomnia'
- GPP does not support logout or shutdown
- GPP does not provide a separate policy for when nobody is logged on
- GPP does not include any monitoring or feedback system
- GPP does not support schedule based power policies
- GPP must be configured from a Windows Vista, Windows 7 or Windows 2008 client PC
Can PowerMAN be deployed in a pre-built software image or 'Ghost'-style deployment?
PowerMAN fully supports deployment in a pre-built software image. This is sometimes known as
a ‘Ghost’-style deployment. Typically, in this scenario, PowerMAN is manually installed
on a master computer and configured with the desired settings. This computer is then
cloned on to multiple destination computers. There is one important thing to remember
when performing such a deployment:
Remember: The ClientGUID setting is used to uniquely identify each computer.
This is automatically generated and should not be cloned from one computer to another.
If this field is removed PowerMAN will generate a unique new ClientGUID. If the same
ClientGUID is present on multiple computers this will prevent the reporting feature
from operating correctly. Please remember to remove the ClientGUID prior to creating
the master software image. The easiest way to do this is to stop the PowerMAN service
and then use the RegEdit tool to delete the setting from the HKLM/Software/PowerMAN
registry key. This step should be performed just prior to creating the software image.
This process is further explained
here.
How can I do a small PowerMAN deployment without Group Policy or similar?
PowerMAN is designed for automated large scale deployment to many computers. This is
normally achieved using Windows Group Policy, SMS, ZENWorks or a similar tool. Sometimes
it may not be possible to use one of these methods. If this is the case PowerMAN can be
deployed manually using the following technique. This method is more time consuming but
ideal for a small scale or trial deployment to a handful of computers.
The PowerMAN deployment requires the following on each PC:
- PowerMAN settings configured
- PowerMAN service installed
The simplest way to configure the settings on each PC is to use the supplied ADM file
and local Group Policy. This is described at the end of the PowerMAN Administrator Guide
in the section
Alternative Configuration Method - Local Group Policy / Registry Settings.
PowerMAN will work best if the settings are present before the service is installed.
If the service is installed first the PC must be rebooted (or the service restarted)
for PowerMAN to become operational. The minimum settings required are described in the
software manual.
The PowerMAN service may be manually installed on each PC using the supplied MSI file.
To perform such an installation (after configuring the settings) simply double click
on the MSI file and follow the on-screen prompts.
PowerMAN can be removed from a PC using the reverse technique. To uninstall PowerMAN
simply double click on the MSI file (again) and follow the on-screen prompts or use
the option available in Control Panel / Add + Remove Programs.
We regularly re-image our computers or dual-boot them. How many licenses do we need?
The PowerMAN client software is licensed based upon the number of concurrent computers running the software
at any one time. You are free to re-use PowerMAN licenses provided that the number of simultaneous
computers does not exceed your licensed limits. The client software does not include an "activation"
requirement and you are welcome to install the software twice on a dual-boot system.
Similarly, you are free to record historic information about any number of computers in
your PowerMAN Enterprise Server database as long as the number of computers reporting at any one
time does not exceed your licensed limit. This feature can be very useful over time because it
allows historic information to be retained as computers are naturally replaced.
Please remember that you will need to confirm the number of computers currently running
PowerMAN when obtaining an updated product key or technical support.
Does PowerMAN save my documents before saving energy?
PowerMAN offers several low-power modes. The sleep and hibernate modes (collectively known as ‘suspend’) preserve
any open programs and documents. The user may continue with their work immediately after the system has resumed.
Optionally the user may be asked for their password when the system resumes.
In some circumstances, such as an open access area, it may not be appropriate to use sleep or hibernate whilst
a user is logged on. In this scenario PowerMAN may be used to log the user off first and then enter a low power state.
PowerMAN may also be used to fully shutdown (power-off) the PC. This generally used when nobody is logged on.
A full shutdown does not preserve the user’s session and they must therefore logon again and re-open any documents
or programs.
The
available low-power modes are described here.
Will power management cause power surges or blow fuses?
No. When a PC is turned on the PSU can draw more power than at any other time.
This happens for a fraction of a second and occurs as the PSU capacitors 'charge' up.
If many computers (>10) are on the same circuit / phase and all turn on at EXACTLY the same
time this can cause a demand surge and ultimately may blow a fuse or trigger a circuit breaker.
In practice, this is
VERY unlikely to be a problem with PowerMAN because:
- It would only occur when using scheduled wake-up from the full shutdown (power-off) or hibernated state. Computers in the standby (sleep) state already have active power supplies.
- The schedule wake feature is only as accurate as the internal PC clock. In practice this is commonly +/- 5 seconds and it is very unlikely that a significant number of computers will all start at exactly the same time
If this problem is perceived to be a significant concern then the following should be considered:
- This is a hypothetical problem. We have never seen this in a live deployment
- It may cost over £50 a year to 'play safe' and avoid this scenario completely
- The probable worst case is a blown fuse. It is unlikely to cause any other damage
- Wake-up times can always be staggered for different groups of computers