IBM DS4700 manual Verifying the Link Rate setting

vIf the Drive fault LED stays on or the Drive activity LED stays off, the new E-DDM might be faulty or might be an uncertified drive. See the DS4000 Storage Manager software for problem determination. In the case of an uncertified drive, verify that the drive options or drive FRU part number is correct for your storage subsystem.

8.Use the DS4000 Storage Manager software to monitor the status of the new E-DDM and the progress of the data reconstruction. Wait for data reconstruction to finish (the Drive activity LED stops flashing).

Note: The Drive activity LED will continue to flash after reconstruction is finished if there is I/O activity to that E-DDM. In that case, use the host software to determine if the data reconstruction is finished.

9.When reconstruction is finished on the new E-DDM, repeat step 5 on page 160 through step 8 for each additional E-DDM that you want to install.

10.Use the DS4000 Storage Manager software to configure the additional space on the new E-DDMs.

Verifying the Link Rate setting

If a link rate problem is indicated, use the following procedure to verify the Link

Rate setting.

A Link Rate switch is located on the front of the storage subsystem as shown in Figure 113 on page 163. The Link Rate indicator LEDs are located on the back of the storage subsystem. The Link Rate switch enables you to select the data transfer rate between the controllers and the drives to either 2 Gbps or 4 Gbps. The Link Rate switch is only read when the storage subsystem is powered up.

Note: Do not mix storage subsystems with different Link Rate speed settings in the same drive loop.

The DS4700 Express Storage Subsystem drive channel operates at either 2 or 4 Gbps fibre channel interface speed. The DS4700 Express Storage Subsystem SATA E-DDM CRUs have an ATA translator card that converts E-DDM 3 Gbps SATA drive interface protocol to either 2 Gbps or 4 Gbps fibre channel interface protocol. It is recommended that the DS4700 Express enclosure speed is set at 4 Gbps when these SATA E-DDM CRUs are installed and connected to storage expansion enclosures running at 4 Gbps speed. The Link Rate setting speed must be set accordingly. See “Verifying the Link Rate setting ” for more information.

Do not mix 2 GB drives and 4 GB drives in the same storage subsystem. If drives of mixed speeds reside in the storage subsystem, the data transfer rate changes depending on the configuration. Table 50 on page 162 shows the data transfer rates for drives of different configurations.

CAUTION:

Do not change the Link Rate setting while the storage subsystem is running. Changing the Link Rate setting while the storage subsystem is running could cause drives to fail. You must power down the storage subsystem and storage expansion enclosures before changing the Link Rate setting.

Chapter 5. Replacing components 161