HP XP P9000 RAID Manager User Guide (T1610-96059, January 2014)

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
SecondaryPrimaryPairing StatusP-VOL
Status
R/W disable
1
R/W enabledUnpaired (Snapshot) volumeSMPL
R/W disableR/W enabledThe Snapshot available state allocated the resource.PAIR (PFUL)
R/W disableR/W enabledThe preparing state allocates the resource for the Snapshot.COPY
R/W disableR/W enabledThe copying state from Snapshot to the primary volume by using
restore option.
RCPY
R/W enabledR/W enabledThe differences of the updated data of the primary and
secondary volume are controlled with copying on write.
PSUS
(PFUS)
R/W disableR/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