The following table lists the pair status (in the upper row) and I/O mode (in the lower row) in phases 1 to 6 of a failure occurrence during data migration.
| Phase of failure occurrence | Volume | Source GAD pair | Temporary GAD pair created for migration | Target GAD pair | |||
|---|---|---|---|---|---|---|---|
| Before the failure | After the failure | Before the failure | After the failure | Before the failure | After the failure | ||
| 1. Creating a temporary GAD pair for migration | P-VOL | PAIR Mirror(RL) |
PSUE Block |
COPY Mirror(RL) |
PSUE Local |
||
| S-VOL | PAIR Mirror(RL) |
SSWS1
Local |
COPY Block |
No change | |||
| 2. Creating a target GAD pair | P-VOL | PAIR Mirror(RL) |
PSUE Block |
COPY Mirror(RL) |
PSUE Local |
COPY Mirror(RL) |
No change |
| S-VOL | PAIR Mirror(RL) |
SSWS1
Local |
COPY Block |
No change |
COPY Block |
No change | |
| 3. Suspending the source GAD pair (at the P-VOL) | P-VOL | PSUS Local |
No change | COPY Mirror(RL) |
PSUE Local |
COPY Mirror(RL) |
No change |
| S-VOL | SSUS Block |
No change | COPY Block |
No change |
COPY Block |
No change | |
| 4. The temporary GAD pair is migrated to PAIR | P-VOL | PSUS Local |
No change | PAIR Mirror(RL) |
PSUE Block |
COPY Mirror(RL) |
No change |
| S-VOL | SSUS Block |
No change | PAIR Mirror(RL) |
PSUE1
Block |
COPY Block |
No change | |
| 5. Suspending the temporary GAD pair (at the S-VOL) | P-VOL | PSUS Local |
No change | PSUS Block |
No change |
COPY Mirror(RL) |
No change2 |
| S-VOL | SSUS Block |
No change | SSWS Local |
No change |
COPY Block |
No change2 | |
| 6. The target GAD pair is migrated to PAIR | P-VOL | PSUS Local |
No change | PSUS Block |
No change |
PAIR Mirror(RL) |
No change |
| S-VOL | SSUS Block |
No change | SSWS Local |
No change |
PAIR Mirror(RL) |
No change | |
Notes:
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