If a server cannot access a pair volume whose status is PAIR, though no SIM has been issued, a failure might have occurred between the server and the storage system. The following topics provide procedures for recovering of the physical path between the server and the storage systems.
The following table shows transitions for pair status and I/O mode, the volumes that are accessible from the server, and the location of the latest data when you can no longer use a physical path between the server and a storage system.
Before failure |
After failure |
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|---|---|---|---|---|---|---|
Pair status and I/O mode |
Pair status and I/O mode |
Volume accessible from the server* |
Volume with latest data |
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P-VOL |
S-VOL |
P-VOL |
S-VOL |
P-VOL |
S-VOL |
|
PAIR (Mirror (RL)) |
PAIR (Mirror (RL)) |
PAIR (Mirror (RL)) |
PAIR (Mirror (RL)) |
OK |
OK |
Both P-VOL and S-VOL |
PAIR (Mirror (RL)) |
PAIR (Block) |
PAIR (Mirror (RL)) |
PAIR (Block) |
OK |
NG |
Both P-VOL and S-VOL |
COPY (Mirror (RL)) |
COPY (Block) |
COPY (Mirror (RL)) |
COPY (Block) |
OK |
NG |
P-VOL |
PSUS/PSUE (Local) |
SSUS/PSUE (Block) |
PSUS/PSUE (Local) |
SSUS/PSUE (Block) |
OK |
NG |
P-VOL |
PSUS/PSUE (Block) |
SSWS (Local) |
PSUS/PSUE (Block) |
SSWS (Local) |
NG |
OK |
S-VOL |
* If failures occur in all servers that access the P-VOL or S-VOL, then you cannot access either volume. |
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SIMs
- Primary storage system: None
- Secondary storage system: None
- Recover the path between the server and the storage system.
- Recover the path from the server to the pair volume.