Chapter 6. ESS Copy Services and Linux 71
Figure 6-8 Incremental FlashCopy
When FlashCopy is established for a large number of volumes, there is a finite amount of
time between the first and last establish, so that copies may not be created at a consistent
point-in-time. FlashCopy V2 introduces a
Consistency Croup
function, which can be used to
create a consistent point-in-time copy across multiple volumes.
6.5 ESS Copy Services Web User Interface
The ESS Copy Services that runs in the ESS provides a Web interface that can be used to
invoke and manage the ESS copy functions. First, one ESS has to be defined as the ESS
Copy Services Server (CSS), and this will hold all ESS Copy Services related information.
Optionally, there can be a second ESS defined to be the backup ESS Copy Services Server.
The recommendation is to define the Copy Services server at the remote (recovery) site and
the backup CSS at the primary (application) site. Setting up the CSS in the ESS is done by an
IBM Service Support Representative.
To access the Copy Services Web User Interface (WUI) you first open the ESS Welcome
Screen, discussed earlier in 4.3.3, “ESS Specialist” on page 44
,
and shown in
Figure 6-9.
FlashCopy initiated from volA to
volB, change recording starts on
both volumes.
Background copy task copies data
from volA to volB.
Time
volA volB
volA volB
volA volB
volA volB
Once FlashCopy is established,
independent updates can proceed
to volA and to volB.
Incremental FlashCopy initiated
from volA to volB.
Background copy task copies
changed tracks from volA to volB.
Change recording reset to track
new changes (ready for the next
incremental FlashCopy request).
72 Linux with zSeries and ESS - Essentials
Figure 6-9 ESS Welcome screen
You then select Copy Services, which will connect your browser to the ESS that is specified
as the Copy Services server. The main menu of the ESS Copy Services Web User Interface
will be displayed (refer Figure 6-10).
Figure 6-10 Main menu ESS Copy Services Web User Interface
Chapter 6. ESS Copy Services and Linux 73
From the Copy Services main menu, you can access all ESS Copy Services panels by
selecting one of the buttons on the left hand side. We will briefly look at each of these. For
further details please refer to
IBM TotalStorage Enterprise Storage Server Web Interface
User’s Guide,
SC26-7448, and
Implementing ESS Copy Services with IBM eServer zSeries,
SG24-5680.
The Volumes panel
The Volumes panel is shown in Figure 6-11. From this panel you can:
򐂰 Receive information and the status of volumes defined in a logical subsystem (LSS) of the
ESS
򐂰 Select source and target volumes for a PPRC or FlashCopy task
򐂰 Filter the output of the volume display to a selected range
򐂰 Search for a specific volume based on its unique volume ID
򐂰 Establish, terminate, and suspend PPRC copy pairs and optionally save the task
򐂰 Establish and withdraw FlashCopy pairs and optionally save the task
򐂰 Enter the multiple selection mode for PPRC and FlashCopy
Figure 6-11 Volumes panel
The Logical Subsystems Panel
The Logical Subsystems panel is shown in Figure 6-12. This panel displays the ESSs and the
logical subsystems within the ESS storage network; the storage network includes all ESSs
that are configured to use the same ESS Copy Services Server. From the Logical
Subsystems panel you can:
򐂰 View all ESSs within the storage network
򐂰 View all logical subsystems (LSSs) within the storage network
򐂰 Get information about a logical subsystem and its status
򐂰 View and modify the copy properties of a logical subsystem
򐂰 Filter the output of a selected range
򐂰 Search for a specific logical subsystem based on its unique address
򐂰 Establish, terminate, and suspend PPRC copy pairs, and optionally save the task
74 Linux with zSeries and ESS - Essentials
򐂰 Perform operations on consistency groups
Figure 6-12 Logical Subsystems panel
The Paths panel
A path is used to send data between the primary and secondary PPRC pairs. The physical
path consists of the ESCON connection between two ESSs, while a logical path describes
the connection of the PPRC source and targets. Please note that before you can create
PPRC copy pair relationships, you must use the Paths panel to establish logical paths
between the source and target LSSs. The Paths panel is shown in Figure 6-13. From this
panel you can:
򐂰 Establish PPRC paths
򐂰 Remove PPRC paths
򐂰 Create a PPRC consistency group
򐂰 View information about paths

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