Suspend types – HP StorageWorks XP Remote Web Console Software User Manual

Page 33

Advertising
background image

Table 4 URz Data Volume Pair Status (continued)

Description

Pair Status

The pair is prepared for delta resync operation. When the
status of primary data volume is Hold, the write data for
the TCz Synchronous R-VOL is stored in the master journal
volume.

Only the delta resync operation, releasing operation, or
changing pair option operation are allowed on the pairs
in Hold status.

Hold

An error occurred on the pair in Hold status. When the
status of primary data volume is Hlde, the write data for
the TCz Synchronous S-VOL will not be stored in the master
journal volume.

Only recovering pair status to standby (Hold) operation,
releasing operation, or changing pair option operation
are allowed on the pairs in Hlde status.

Hlde

Suspend Types

“Suspend Types” (page 34)

lists and describes the URz suspend types, which indicate the reason

for the suspension. A URz pair can be suspended by the user at any time after the initial copy
operation is complete. The user must suspend a URz pair in order to perform ICKDSF maintenance
on the primary data volume or to access the secondary data volume (read only mode).

When a URz pair is suspended by the user, the primary storage system and secondary storage
system ensure synchronization by either completing or discarding any pending update copy
operations according to the user-specified drain/purge suspend option.

A URz pair is suspended by the primary storage system when the following suspension conditions
are detected. A URz pair can also be suspended by the secondary storage system (see

Suspension

Condition

).

When the primary storage system detects that the user has released the volume pair from the
secondary storage system (for example, to access an secondary data volume at the secondary
site),

When the primary storage system detects an error condition related to the secondary storage
system, secondary data volume, or a URz journal data operation,

When the secondary storage system cannot execute DFW (DASD fast write) to the secondary
data volume (only if DFW required is selected), or

When the primary storage system is unable to communicate with the secondary storage system.

For more information on URz journal data operations, see

Suspension Condition

.

When a URz pair is suspended, the primary storage system stops performing update copy operations
to the secondary data volume. Moreover, the primary storage system and secondary storage system
keep track of any journal data that were discarded during suspension, and the primary storage
system continues accepting write I/Os for the primary data volume and keeps track of the primary
data volume tracks which are updated while the pair is suspended.

A suspended URz secondary data volume has an additional status called the consistency status
which is displayed only at the secondary storage system. The consistency status of a suspended
URz secondary data volume indicates its update sequential consistency with respect to the other
secondary data volumes in the same group.

“URz Suspension Condition” (page 35)

lists and describes the consistency status descriptions for

suspended URz secondary data volumes.

When a URz pair is suspended, whether user-requested or due to failure, the primary storage
system generates sense information to notify the host(s).

URz Data Volume Pair Status

33

Advertising
This manual is related to the following products: