Snapshot pair status – HP XP P9500 Storage User Manual

Page 154

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A Fast Snap pair is generated in the following two cases:

When a V-VOL (OPEN-0V) is specified as an S-VOL.

When a pool for Fast Snap is specified as the pool type.

A Fast Snap pair is generated in the following two cases:

When a V-VOL (OPEN-0V) is specified as an S-VOL.

When a pool for Fast Snap is specified as the pool type.

A V-VOL has the following characteristics:

It appears as "OPEN-0V" to identify a V-VOL easily via the SCSI Inquiry or RAID Manager.

A V-VOL unmapped to the S-VOL of a Snapshot will reply to a SCSI Inquiry, but Reading
and/or Writing is not allowed. LDEV will reply the capacity setting as an LU to SCSI Read
Capacity.

A V-VOL that has become the S-VOL of a Snapshot will reply to a SCSI Inquiry, and Reading
and/or Writing is allowed.

Snapshot pair status

Each paired volume consists of a primary volume (P-VOL) and a secondary volume (S-VOL). Each
volume has the status for controlling the pair state.

The P-VOL controls the pair state that is reflected on the status of the S-VOL. The major pair statuses
are "SMPL", "PAIR", "PSUS", "COPY", and "RCPY". The status is changed when the RAID Manager
command is issued. A read or write request from the host is allowed or rejected according to the
status.

Table 36 Snapshot Pairing Status

Secondary

Primary

Pairing Status

P-VOL
Status

R/W disable

1

R/W enabled

Unpaired (Snapshot) volume

SMPL

R/W disable

R/W enabled

The Snapshot available state allocated the resource.

PAIR (PFUL)

R/W disable

R/W enabled

The preparing state allocates the resource for the Snapshot.

COPY

R/W disable

R/W enabled

The copying state from Snapshot to the primary volume by using
restore option.

RCPY

R/W enabled

R/W enabled

The differences of the updated data of the primary and
secondary volume are controlled with copying on write.

PSUS
(PFUS)

R/W disable

R/W enabled

2

"PSUS" status owing to an internal failure. The differences of
the updated data for the Snapshot volume are not controlled.

PSUE
(Error)

Notes:

1.

V-VOL unmapped to the S-VOL of a Snapshot will reply to a SCSI Inquiry, but Reading and/or Writing is not
allowed.

2.

Reading and writing are enabled, as long as no failure occurs in the primary volume.

154 Data replication operations with RAID Manager

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