HP StorageWorks XP Remote Web Console Software User Manual

Page 41

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

“Suspension Condition” (page 42)

).

When the primary storage system detects that the user has released the volume pair from the
secondary storage system (for example, to access a 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 Universal Replicator for Mainframe journal data operation,

When the secondary storage system cannot execute DFW 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 Universal Replicator for Mainframe journal data operations, see

“Suspension Condition” (page 42)

.

When a Universal Replicator for Mainframe 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 Universal Replicator for Mainframe secondary data volume has an additional status
called the consistency status which is available only at the secondary storage system. The consistency
status of a suspended Universal Replicator for Mainframe secondary data volume indicates its
update sequential consistency with respect to the other secondary data volumes in the same group.

“Universal Replicator for Mainframe Suspension Condition” (page 43)

lists and describes the

consistency status descriptions for suspended Universal Replicator for Mainframe secondary data
volumes.

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

Table 6 Suspend Types

Description

Applies to

Suspend Type

The user suspended the pair from the primary storage system or
secondary storage system using the secondary data volume option.

Primary data
volume, secondary
data volume

Secondary
data volume
by operator

The secondary storage system received a request from the primary
storage system to suspend the volume pair. The primary data volume

Secondary data
volume

By MCU

suspend type is Primary data volume by Operator or Secondary
data volume by Operator
.

The primary storage system detected an error condition at the
secondary storage system which caused the primary storage system

Primary data volume

By RCU

to suspend the Universal Replicator for Mainframe volume pair. The
secondary data volume suspend type is By MCU.

The primary storage system detected that the secondary data volume
status changed to simplex because the user released the pair from

Primary data volume

Delete Pair to
RCU

the secondary storage system. The pair cannot be resumed because
the secondary data volume does not have the suspended status.

The primary storage system detected an error during communication
with the secondary storage system or an I/O error during update

Primary data volume

Secondary
Data Volume
Failure

copy. In this case, the secondary data volume suspend type is usually
By MCU.

Pair Status

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