Timer type option, Journal group operations, Urz delta resync operation – HP StorageWorks XP Remote Web Console Software User Manual
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Timer Type Option
The timer type option allows you to specify the method applied by the primary storage system to acquire
the time-stamp information for each journal data. The following timer types are available for selection:
•
System. When the System timer option is selected, the primary storage system acquires the
time-stamp information for each journal data as follows. When a URz pair is established, the
primary storage system reports state-change-interrupt (SCI) to all hosts. The host then issues
a series of sense group commands to determine the device status change, and the primary
storage system returns the same response as if the device had been added to an XRC session to
activate I/O time-stamping for the device. Once I/O time-stamping is activated, the MVS IOS
routine attaches the time-stamp information (contents of time-of-day (TOD) clock) to each write
I/O operation for the device. The time-stamp indicates the time that the update was generated
during start sub-channel (SSCH) at the main host system, and the time-stamp is transferred to the
primary storage system at the beginning of each I/O operation.
•
Local. When the Local timer option is selected, the primary storage system does not acquire
time-stamp information from the host I/O time-stamping function.
•
None. This timer option can be selected only when the copy direction of a URz volume pair is in
reverse direction (i.e., from the secondary site to the primary site).
When the None option is selected, the primary storage system acquires time-stamp information from
the host I/O time-stamping function.
Journal Group Operations
URz provides the following group-based operations to simplify and expedite disaster or failure recovery
procedures:
•
Group operations at the primary subsystem.
• Split all pairs in a journal group. See
Splitting a Mirror (Suspending a copy operation)
for a description of the Suspend Range-Group suspend pair option.
• Resume all suspended pairs in a journal group. See
Restoring a Mirror (Resuming a copy operation)
” on page 143 for a description of the URz
Resume Range-Group resume pair option.
• Delete all pairs in a journal group.
Deleting Data Volumes from a Mirror (Ending a copy operation)
” on page 144 for a
description of the Delete Range-Group delete pair option.
•
Group operations at the secondary subsystem
• Split (suspend pair) all pairs in a journal group. See
Splitting a Mirror (Suspending a copy operation)
” on page 142 for a
description of the Suspend Range-Group suspend pair option.
• Delete (delete pair) all pairs in a journal group regardless of their consistency status. See
Deleting Data Volumes from a Mirror (Ending a copy operation)
” on page 144 for a
description of the Delete Range-Group delete pair option.
URz Delta Resync Operation
When you are using URz and TCz Synchronous in a 3DC multi-target configuration, URz
provides delta resync operation as one of the solutions for failures in primary site. In a 3DC
multi-target configuration, there are one primary site and two secondary sites; TCz Synchronous
and URz secondary sites. For detailed information about 3DC multi-target configuration, see
TCz Synchronous (3DC Multi-target Configuration)
If a failure occurs on the primary site in 3DC multi-target configuration, you need to use Business
Continuity Manager to use the TCz Synchronous secondary site as the primary site. If you perform a
delta resync operation after the TCz Synchronous secondary site becomes a primary site. The URz pair
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Overview of Universal Replicator Operations