IBM TotalStorage DS8000, Руководство пользователя

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Note: For details on individuals tasks, see the related topics section.
1. Quiesce host I/O that is updating the primary volumes that is located in the
local site.
2. Check the status of Global Mirror to ensure that Global Mirror is in a good
state and that a consistency group has formed successfully at the desired
interval.
3. Wait until two consistency groups form successfully.
4. Pause Global Mirror and suspend the Global Copy pairs (A->B).
5. Create paths from the B volumes to the A volumes.
6. Perform recovery failover on the B volumes (B->A).
7. Perform the fast reverse restore process from the C volumes to the B volumes,
selecting the Initiate background copy option.
Note:
a. When you initiate the fast reverse restore process, Volume C
becomes unusable.
b. There must be no I/O allowed to the B or C volumes during the fast
reverse restore process.
8. Wait for the background copy to complete before continuing to the next step.
The C to B FlashCopy relationship ends when the background copy
completes.
9. Initiate the FlashCopy from Volume B back to Volume C. Ensure that you also
select the Enable Change Recording and Inhibit writes to target volume
options. This creates a backup copy of the consistency group before
applications begin to update the B volumes.
10. Start the host I/O at the remote site on the B volumes. You will remain in
production on the remote site in this configuration until you are ready to return
production to the local site.
11. When you are ready to return production to the local site, perform recovery
failback (B->A) to resynchronize the A volumes. The application at the remote
site remains active.
12. After the resynchronize process has completed its first pass, quiesce the
applications at your remote site so that the resynchronization can complete.
13. When the resynchronization has completed (no out-of-sync tracks), perform
recovery failover and failback with Global Copy on Volume A to re-create the
Volume A to Volume B Metro Mirror relationship.
14. Start the host I/O at the local site on the A volumes.
15. Resume the Global Mirror process.
Using Global Mirror for an unplanned failover and failback
Use this process to manage an unplanned failover and failback that involves two
sites which are referred to as the local (or production) and remote (or recovery)
sites.
Global Mirror provides two-site extended distance remote copy disaster recovery.
When a disaster occurs at the local site, you must initiate the failover and failback
recovery of consistent data on the remote site. Host activity can resume on the
local site when the host recovers but not before a consistent set of data is copied to
all primary volumes on the local site.
Chapter 10. Disaster recovery using Copy Services
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