Note: The information in this section is specific to POWER-based.
Users of Power Management need to
be aware of the following limitations:
|Changing configuration during suspend/hibernation||Altering the system configuration, such as memory size, devices, and so on, while the system is in the suspend or hibernation state can cause unpredictable results. This could cause loss of data, file system corruption, system crashes, or a failure to resume from the suspend or hibernation state.|
|Non-PM-aware device drivers||If a device driver is installed that is not Power Management-aware,
unpredictable results could occur when resuming from suspend or
hibernation. If a non-PM-aware device driver is to be installed, the
suspend and hibernation states must never be used. The following
command can be run with root authority to disable the suspend and hibernation
states effective on the next system startup.
|Booting from CD-ROM or other media after hibernation||Accessing the rootvg from maintenance mode such as CD-ROM startup when a valid hibernation image exists can result in loss of data and file system corruption.|
|Network connections during suspend/hibernation||Network connections are disconnected during the suspend and hibernation
states. These connections might have to be re-established by the user
after resuming. Because locally cached data is not available to other
nodes on the network during this time and network activity cannot be monitored
by the local node during this time, do not use the suspend and hibernation
states when using network interfaces such as TCP/IP, NFS, AFS, DCE, SNA, OSI,
NetWare, NetBIOS, and so on.
|Power Button Behavior||When Power Management is enabled, the power button is software
controlled. If there is some sort of system problem, the software
necessary to make the requested Power Management state transition using the
power switch might not be able to run. In such a situation, or whenever
necessary, it is always possible to turn off the power immediately by pressing
the power button three times quickly (within a two second period). This
overrides whatever state transition has been selected for the power switch,
and requires a full restart.
In addition, if the Power Management daemon (/usr/bin/pmd) is never started (by an entry in /etc/inittab by default), the power switch acts as if there were no power management. A single button press turns off the system. If /usr/bin/pmd is started and then stopped, the first two button presses are ignored, and the third turns off the system. These button presses can be over any period of time as long as /usr/bin/pmd is not restarted.