Use this process to set up the environment to use Metro/Global Mirror.
To set up a Metro/Global Mirror Configuration, the remote site volumes do not have to be connected to the host site. The local and intermediate site volume needs to be connected to the site where the commands are going to be issued. If the intermediate site volumes are connected to an intermediate site system only, the Global Mirror setup commands are issued. If the local site has connectivity to the intermediate site and local site volume, then all of the commands can be issued from the local site.
Connect to the storage units to be used for System z® or open systems host system storage.
Configure the following Metro/Global Mirror environment, which
uses three sites (local, intermediate, and remote) and a minimum of
four volumes (volume A, volume B, volume C, and volume D) on three
storage units. For ease of description, the Metro/Global Mirror configuration
is described in terms of A, B, C, and D volumes. Some environments
can contain hundreds or thousands of volumes. See Figure 1 for a high-level view of how the volumes
are configured in a Metro/Global Mirror environment.
Figure 1. Metro/Global Mirror volume configuration
Before you set up a Metro/Global mirror configuration,
do the following steps:
- Establish paths before you can establish pairs or start a session.
- Define a session to an LSS before you can add any volumes to the session.
To set up the environment to use Metro/Global Mirror, use the following process:
- Establish paths between A volumes' LSSs and B volumes' LSSs.
- Establish paths between B volumes' LSSs and C volumes' LSSs.
- Establish paths from control unit that is the intended master of the Global Mirror session at the intermediate site and the intended subordinate control units at the intermediate site.
- Define Global Mirror session to all LSSs that are going to participate in the session at the intermediate site.
- Establish B volumes to C volumes Global Copy (PPRC-XD) relationships with the cascading and NOCOPY options.
- Establish A volumes to B volumes PPRC relationships with the new option for change recording.
- Establish C volumes to D volumes FlashCopy® relationships, using ASYNC in the MODE keyword (for the Global Mirror remote site consistent copy) after the A volumes to B volumes relationships have reached a full duplex status.
- Join the B volumes to the Global Mirror session.
- Start the Global Mirror session.