Controller settings for IBM System Storage DS5000 and IBM DS4000 systems

Controller settings are the settings that apply across one IBM® System Storage® DS5000 or IBM DS4000® system.

You must configure the following settings for IBM System Storage DS5000 and IBM DS4000 systems:

Depending on your model, you must set either the default host type of your IBM System Storage DS5000 or IBM DS4000 system, or the host type of the chosen partition, to one of the following:
```
IBM TS SAN VCE
SAN Volume Contr
```
Perform one of the following tasks to set the host type:
- Click Storage Subsystem > Change > Default Host Type
- For each host port, specify the host type of that port or modify existing ports.
Set the system so that both controllers have the same worldwide node name (WWNN). See the following Web site for the scripts that are available to change the setup for IBM System Storage DS5000 and IBM DS4000 systems:
www.ibm.com/storage/support/
Ensure that the AVT option is enabled. The host type selection should have already enabled the AVT option. View the storage system profile data to confirm that you have the AVT option enabled. This storage profile is presented as a text view in a separate window. See the following Web site for the scripts that are available to enable the AVT option:
www.ibm.com/storage/support/
You must have the following options enabled on any logical units that are mapped to IBM System Storage DS5000 and IBM DS4000 systems:
- read caching
- write caching
- write cache mirroring
You must not have caching without batteries enabled.