[ Contents ] [ Index ]

Adding a New Logical Drive or Adding a Logical Volume From New Logical Drives

Use this option to add one or more new logical drives to an existing configuration of RAID sets or to add a logical volume from new logical drives. To add a logical volume from existing logical drives, see Adding a Logical Volume From Existing Logical Drives.

NOTE: Logical volumes are unsuited to some modern configurations such as Sun Cluster environments, and do not work in those configurations. Use logical drives instead.

NOTE: If the logical drive is going to be larger than 253 Gbyte, see Preparing for Logical Drives Larger Than 253 Gbyte.

  1. Select the array that you want to configure.
  2. Choose Configuration > Custom Configure.
  3. NOTE: This selection is inactive unless you have selected a controller with available physical drives.

  4. Select Add LDs/LVs to the Current Configuration from the Custom Configuration Options window.

  5. Verify that the server and controller displayed at the top of the window are correct.

  6. Select a disk you want to be included in the new logical drive and click Add Disk.
  7. If you make a mistake or change your mind, select the drive in the participating drives list and click Remove Disk.

  8. Select a RAID level. For definitions of the RAID levels, see RAID Levels.

  9. Select the Host channel and ID to which you would like your new logical drive to be mapped to from the Channel and the ID list boxes.
  10. Set the Max Drive Size.

    The Max Drive Size displays the total capacity of each disk. A smaller logical drive can be created by decreasing this value.

    NOTE: If you do not change the Max Drive Size but you do change the Partition Size, a new partition is created at the specified partition size. Remaining capacity can be used later by expanding the drive (as explained in Expanding the Capacity of a Logical Drive). The drive capacity is no longer editable after a partition is created.

    NOTE: If you want to create another logical drive on the same controller, click New LD. The logical drive you just defined is created and you are returned to the top of the window, enabling you to create another logical drive.

  11. (Solaris OS only). If you want the new logical drive to be automatically labeled, which enables the OS to use the drive, click Write a new label to the new LD.

  12. To use the logical drive immediately, select On-line Initialization.

    Because logical drive initialization can take up to several hours, you can choose to initialize a logical drive on-line. On-line initialization enables you to begin configuring and using the logical drive before initialization is complete. However, because the controller is building the logical drive while performing I/O operations, initializing a logical drive on-line requires more time than off-line initialization.

    If you do not select On-line initialization, you can configure and use the drive only after initialization is complete. Because the controller is building the logical drive without having to also perform I/O operations, off-line initialization requires less time than on-line initialization.

    NOTE: On-line Initialization does not apply to logical volumes.

  13. Select the Stripe Size.

    Select Default to assign the stripe size per Optimization mode as specified in the default stripe size table shown in Changing Controller Parameters - Cache tab, or select a different stripe size.

    Once the stripe size is selected and data is written to logical drives, the only way to change the stripe size of an individual logical drive is to back up all its data to another location, delete the logical drive, and create a logical drive with the stripe size that you want.

  14. Specify Default, Write-through, or Write-back as the Write Policy for the logical drive.

    The write policy determines when cached data is written to the disk drives. The ability to hold data in cache while it is being written to disk can increase storage device speed during sequential reads. Write policy options include write-through and write-back.

    Using write-through cache, the controller writes the data to the disk drive before signaling the host OS that the process is complete. Write-through cache has lower write operation and throughput performance than write-back cache, but it is the safer strategy, with minimum risk of data loss on power failure. Because a battery module is installed, power is supplied to the data cached in memory and the data can be written to disk when power is restored.

    Using write-back cache, the controller receives the data to write to disk, stores it in the memory buffer, and immediately sends the host OS a signal that the write operation is complete, before the data is actually written to the disk drive. Write-back caching improves the performance of write operations and the throughput of the controller card. Write-back cache is enabled by default.

    NOTE: The setting you specify you specify in the Write Back field on the Cache tab of the Change Controller Parameters window is the default global cache setting for all logical drives. (See Changing Controller Parameters - Cache tab.)

  15. Click OK.

  16. To add this logical drive to a logical volume, click New LD and see Adding a Logical Drive to a Logical Volume.

  17. When you are satisfied with the selections on this window, and do not want to define another logical drive, click Commit. A confirmation window is displayed showing the new configuration.
  18. Click OK to accept the configuration or Cancel to return to the console.
  19. NOTE: You cannot change a logical drive configuration after you click OK. During initialization LD/LV size is displayed as 0 Mbyte.

  20. (HP-UX OS only). To ensure that the environment is stable and accurate after making configuration changes, you need to run the ioscan -fnC disk command.

    NOTE: If you used System Administrator Manager (SAM) to unmount the file system, make sure it is closed before running the ioscan command.

  21. (IBM AIX OS only). To ensure that the environment is stable and accurate after making configuration changes, you must update the Object Data Manager (ODM) as explained in Updating the Object Data Manager on an IBM AIX host.

    [ Contents ] [ Index ]