IBM TS2340 User Guide - Page 59

AIX Device Driver (Atape) 2. Provide information about which logical devices configured on the system have path failover support enabled. Querying Primary and Alternate Path Configuration You can display the primary and alternate path configuration for all devices with the lsdev command. There may be two or more logical devices configured for a single physical device, but the first device configured is labeled the primary device. All other logical devices configured after the first device are labeled as alternate devices. To see this, run the lsdev -Cc tape command and look at the location field in the data. By running lsdev -Cc tape | grep PRI, for example, you can easily determine how many physical devices on the RS/6000 or System p (also known as pSeries) server are configured with path failover support. Configuring and Unconfiguring Primary and Alternate Devices Logical devices configured as alternate paths can be unconfigured and reconfigured at any time after the initial configuration is run. Unconfiguring an alternate path device removes that device from the primary device path list, removes the ALT appended to the location field, and changes the device to the Defined state. The primary and any other alternate devices are still available. Likewise, configuring a new alternate path device or reconfiguring an existing one in the Defined state adds that device to the primary device path list, appends ALT to the location field, and makes the device available. Logical devices that are configured as primary paths can also be unconfigured and reconfigured at any time after initial configuration is run. However, the operation is different for a primary device. When a primary device is unconfigured, the following events occur: 1. All alternate devices are unconfigured as described previously. 2. The primary device is unconfigured. 3. The PRI appended to the location field is removed. 4. The device is changed to the Defined state. 5. All alternate devices that were unconfigured are reconfigured. The first device that is reconfigured becomes the new primary device. All remaining alternate devices are reconfigured as alternate paths. These methods provide the ability to unconfigure and reconfigure physical devices on the system when device connections or addressing changes are made. System-Managed Encryption Device Driver Configuration System-Managed Encryption can be set on a specific tape drive using the standard SMIT panels to Change/Show Characteristics of a tape device or the command line chdev command. There are 2 new attributes added for encryption: sys_encryption "yes/no" wrt_encryption "off/on/custom" Use System Encryption FCP Proxy Manager System Encryption for Write Commands at BOP The sys_encryption attribute enables device driver system-managed encryption for a tape drive by setting the value to yes. Chapter 3. AIX Tape and Medium Changer Device Driver 41