Turning a tape drive on and off while you mount IBM Storage Archive

How to turn a tape drive on and off when you use IBM Storage Archive.

Before you begin

Before you power on or power off a tape drive, you must first prepare the library. Determine which of the following scenarios applies to your environment by checking the interfaces between the server PC, tape library, and the target tape drive. Then, refer to Table 1 to determine which procedure you need to perform.

Scenario 1: The server PC connects to the target tape drive, and the target tape drive connects to the tape library. In this case, only the target tape drive is used as a control path; but if another control path is established, the control path failover feature is disabled.
Scenario 2: The server PC connects to the target tape drive, and the target tape drive connects to the tape library. In addition, the server PC connects to another tape drive that also connects to the tape library. The target tape drive and the other tape drive establish multiple control paths and the control path failover feature is enabled.
Scenario 3: The target tape drive connects only to the tape library and does not establish a control path.

In addition to these three interface and control path scenarios, the type of host bus adapter (HBA) affects how you do the tape drive power-on or power-off procedure. Refer to Table 1 for details.

Table 1. Drive firmware upgrade procedure options
HBA Type	Target tape drive settings
HBA Type	Scenario 1 (CPF disabled)	Scenario 2 (CPF enabled)	Scenario 3 (no control path)
SAS	Option A	Option A	Option B
Fibre Channel	Option A	Option B	Option B

Procedure

Complete the appropriate step, or steps, based on the options that are presented in Table 1 to successfully remove or restore power from or to a tape drive:

For Option A, complete the following prerequisite and postrequisite steps:
1. Before you turn off the tape drive, stop IBM Storage Archive Enterprise Edition by using the eeadm cluster stop command, as in the following example.
```
eeadm cluster stop -l library_name
```
2. After you turn on the tape drive, start IBM Storage Archive Enterprise Edition by using the eeadm cluster start command, as in the following example.
```
eeadm cluster start -l library_name
```
  For more information, see How to start and stop IBM Storage Archive Enterprise Edition
For Option B, complete the following prerequisite and postrequisite steps:
For control path drive, the control path automatically switches to another one when the target drive control path is cut off.
1. Before you turn off the tape drive, you must disable the target tape drive by using the eeadm drive down command.
2. After you turn on the tape drive, you must enable the tape drive by using the eeadm drive up command.
For the release which doesn't have the eeadm drive down / up command, the eeadm drive unassign / assign command can be used.