Enable a Hibernate Once/Resume Many Environment by Using EWF

3/21/2011

After you add EWF and hibernation to your run-time image, configure hibernation and verify that HORM is enabled.

To enable a Hibernate Once/Resume Many environment that uses EWF

Make sure that your system supports hibernation. You can use the Powercfg Command-Line Options command line tool to enable hibernation.
```
powercfg -h on
```
Add the Enhanced Write Filter with HORM package to your run-time image. For more information see Configure EWF RAM Mode or Configure EWF RAM Reg Mode.
Deploy your image to a computer. See Deploying Images.
Use the EWF Manager command line tool to verify that EWF is enabled.
```
Ewfmgr -all
```
If EWF is enabled, go to the next step. Otherwise, enable EWF. For example:
```
ewfmgr -all -enable
```
Important

You must use the -all command because HORM has a requirement that all volumes must either be protected with EWF or be in unmounted state when the Hibernate Once occurs. This is to prevent state synchronization problems. Each Resume from hibernation expects the entire system to be in exactly the same state as when the Hibernate Once occurred.
Restart the system.
Activate HORM by using the EWF Manager command or the EWF API. For example:
```
ewfmgr c: -activateHORM
```
Open applications and start any processes that you want to be running on the system when it resumes from hibernation.
Hibernate the system.
```
shutdown /h
```
Restart the system. After you restart the system, EWF is enabled.
Verify that HORM is enabled. For example:
```
Ewfmgr
```
You should see the output of the ewfmgr command.