HP OpenVMS Systems Documentation

Content starts here Configuration Tasks
HP Volume Shadowing for OpenVMS: OpenVMS Version 8.4 > Chapter 3 Preparing to Use Volume Shadowing

Configuration Tasks

Once you have determined how to configure your shadow set, perform the following steps:

  1. Select which of your disk drives you want to shadow. Prepare the selected volumes for mounting by physically placing the volumes in the drives (for removable media disks). Ensure the disks are not write locked.

  2. Consider whether to initialize the volumes you have chosen to shadow. Do not initialize volumes that contain useful data.

    If you are creating a new shadow set, you can initialize one volume at a time, or multiple volumes with one command, which can streamline the creation of a shadow set (see “Using INITIALIZE/SHADOW/ERASE to Form a Shadow Set (Integrity servers and Alpha)”). When you initialize one volume at a time, you can give it a volume label to be used for the shadow set. When you later mount additional volumes into the shadow set, each volume is initialized and is given the same volume label automatically.

  3. Install the Volume Shadowing for OpenVMS licenses unless you are running OpenVMS Integrity servers and purchased either the Enterprise Operating Environment or the Mission Critical Operating Environment. These operating environments include the Volume Shadowing for OpenVMS license. See “Licensing Volume Shadowing for OpenVMS ” for more information.

  4. Set the SHADOWING parameter to enable volume shadowing on each node that uses volume shadowing. See “Volume Shadowing Parameters ” for more information.

    Setting the SHADOWING parameter requires that you reboot the system.

  5. Set the ALLOCLASS parameter to a nonzero value. This parameter enables the use of allocation classes in device names. You must include a nonzero allocation class in the device name of shadowed disks. For more information, see “Creating a Shadow Set ”.

  6. Dismount the disk drives you selected for the shadow set and remount them (along with the additional shadow set disk drives) as shadow set members. Note that:

    • You do not need to change the device volume labels and logical names.

    • If you use mount command files, ensure that the commands mount the physical devices using the appropriate naming syntax for virtual units (DSAn:).

For more information on the MOUNT command, see Chapter 4.

System disks can be shadowed. All nodes booting from that system disk must have shadowing licensed and enabled.