Changing Device Information for Tape Stand-Alone Devices

To change device information for an existing tape stand-alone device, take the following steps:

1. Type WRKDEVBRM at a command line and press Enter.
2. At the Work with Devices display, locate the name of the device you want to work with and type a 2 (Change) in the Opt column. This takes you to the Change Tape Device display.

                                   Change Tape Device                              
                                                                                   
    Tape device . . . . . . . . . . . :   TAP01                                    
    Device type/model . . . . . . . . :   6386/001                                 
                                                                                   
    Type changes, press Enter.                                                     
                                                                                   
    Text  . . . . . . . . . . . . . . .   Entry created by BRM configuration       
                                                                                   
    Location  . . . . . . . . . . . . .   *HOME        Name, F4 for list           
                                                                                   
    Use optimum block size  . . . . . .   *YES         *NO, *YES                   
    Next volume message . . . . . . . .   *YES         *YES, *NO                   
    Tape mount delay  . . . . . . . . .   *IMMED       *IMMED, 1-999               
    Auto enroll media . . . . . . . . .   *SYSPCY      *SYSPCY, *NO, *YES          
                                                                                   
    Shared device . . . . . . . . . . .   *NO          *YES, *NO                   
      Shared device wait  . . . . . . .        30      Seconds                     
                                                                                   
                                                                                   
                                                                                   
                                                                           More... 
    F3=Exit   F4=Prompt   F12=Cancel                                               
   

3. Change the parameters as needed. Following are brief summaries of the key parameters on this display:
   • The default value in the Use optimum block size field is *YES. If you want to use this default value, keep the following restrictions in mind:
     • i5/OS cannot duplicate media volumes if the output device uses a block size that is smaller than the blocks being read by the input device.
     • If you use the optimum block size, the system does not compress the data.

     If these restrictions concern you, set the value to *NO. In that case, BRMS uses the default block size that is supported by your device. It is recommended, however, that you use the default value, *YES, whenever possible because the device performs better when writing larger blocks of data at once.

   • The default value in the Auto enroll media field is *NO and is established in the system policy (*SYSPCY). If you want BRMS to automatically enroll media into the tape device you want to use, you can specify *YES at this display.
   • The default value in the Shared device field is *NO. If you want to share a device between multiple systems, change this parameter to *YES, and keep the following information in mind:
     • BRMS manages device availability for shared devices. This means that BRMS varies off the device after use so that it is readily available for use by another system. BRMS varies on all of the devices it needs prior to a save operation. The Shared device wait field specifies how long BRMS should wait for a device to become available if it cannot locate any usable devices.
     • Device pooling happens when several System i® platforms share a single tape drive or set of tape drives. In this case, i5/OS or BRMS picks an eligible device from a pool of devices that supports the read and write densities you need. This permits several System i platforms to access the pool at the same time for any eligible device. In this way, you do not have to wait for a specific device to become available or fail the operation due to a busy device. If you are using a tape library, i5/OS manages device pooling for you. If you are using a stand-alone device, BRMS manages device pooling for you.
   • In the Allow densities field you can indicate the density at which your device can read and write to media. BRMS separates densities into the read and write densities that are allowed by your device. This separation recognizes that some devices can read media to a device but cannot write to it and vice versa. Other devices can read and write the same densities. The ability to specify the densities that a device can read or write is particularly useful when using device pooling. For example, if you are backing up media with a density of 1600 BPI, you can use a 2400-A12 or a 9348-0001 for this operation. BRMS can do this because both devices can write to media at 1600 BPI. You can have multiple devices assigned to a location.
   • After you have changed and reviewed these and other parameters as needed, press Enter to return to the Work with Devices display.