Global Mirror setup (DS Storage Manager)

Use this DS Storage Manager process to set up your environment to use Global Mirror. Global Mirror processing is used for general transactions as well as with data recovery transactions. When Global Mirror is used for data recovery it asynchronously copies data from a host to a recovery site and maintains data on a storage unit at the recovery site.

1. Ensure that the storage units that you are using are configured, assigned, and operating in a normal state. See "Storage Units — Main Page" for details.
2. Ensure that fibre-channel paths are established.
   • All Global Copy source and target pairs
   • Master and subordinate storage units
   Note: To establish a volume pair, there must be a path between the LSSs in which the volumes reside. See "Creating remote mirror and copy paths" for the task procedure.
3. Create Global Copy pairs. Create the volumes from the local storage units to the recovery storage units using the path that you established. See "Creating Metro Mirror volume pairs" for the task procedure.
   Note: When you create volume pairs using Global Copy, data on the volumes is not time consistent and generally not useful for the recovery site unless all of the data from the local site has been copied up to a specific point in time. To be useful for disaster recovery, the target volumes must periodically be made consistent and a copy of the data made. Be aware that the Global Copy source volumes are not active in the Global Mirror session until they have completed the first pass of their initial copy.
4. Create FlashCopy relationships. Create the relationships at the recovery site between the Global Copy secondary volumes and the FlashCopy target volumes. Ensure that you resynchronize all volumes that will be in the FlashCopy relationships. See "Creating a FlashCopy volume pair" for the task procedure. When creating the FlashCopy relationship, select the following options:

   Enable Change Recording

   Select this option to activate change recording on the volume pair participating in a FlashCopy relationship.

   Note: The Persistent FlashCopy option is the default with this option.

   Inhibit writes to target volume

   Select this option to ensure that updates cannot be made to the target volume. This ensures data consistency on the target volume. If you select the Inhibit writes to target option, the change recording feature is not active on the target volume, only on the source volume.

   Note: Do not select the Initiate background copy option so that data will only be copied from the source volume to the target volume if a track on the source volume is modified.
5. Create your Global Mirror session. See "Creating a new Global Mirror session" for the task procedure.
6. Add volumes to your Global Mirror session. See "Adding volumes to a Global Mirror session" for the task procedure.