IBM Enterprise Storage Server 2105 E10, Introduction And Planning Manual

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Services server. If you have planned in advance and have created tasks for
disaster recovery then you can run those tasks and bring your production
systems back up.
Note: In Open Systems environments this setup might have performance
implications because the communications with Open Systems command
line interface (CLI) and the ESS Web Copy Services server is done over
TCP/IP links. If you have enabled ESS Web Copy Services for the
OS/390 environment, you will have the same results.
2. Primary Copy Services server is at your production site
This configuration might be the desirable setup in Open Systems environments.
The reason for this is the Open Systems CLI uses TCP/IP links to communicate
with the host systems and the Web Copy Services Server, which may introduce
network delays. If you have enabled ESS Web Copy Services for the OS/390
environment, you will have the same results.
However, with this configuration, if your primary site fails, there can be delays in
bringing up applications at the recovery site. Because the primary server is at
the production site, you will need to perform manual procedures to enable the
backup server as the active server at the recovery site before you can execute
tasks to begin using the volumes.
Creating tasks for PPRC and FlashCopy
We recommend you create all tasks during setup, and that you name the tasks in
such a way that will be meaningful to you. The Web User Interface will enforce
rules so the names you choose will be compatible with command line invocation.
As the following steps show, each time you create a task, you also need to create
the corresponding tasks to terminate relationships. Why is that a good idea?
Because after a disaster you need to terminate existing relationships to get your
production systems up and running at your recovery site. For further information,
see
IBM Enterprise Storage Server Web Interface User’s Guide .
1. Establish Paths tasks
Step 1a
a. Create tasks for establish groups
b. For Consistency Grouping, select CG
c. Name, and save each task
Step 1b Copy and edit each establish paths task
created in step 1a, to create
a. An associated remove paths task
b. Name, and save each task
2. Establish Pairs tasks
Step 2a
a. Create tasks for establish pairs
b. Name, and save each task
Step 2b For each establish pairs task created in 2a,
copy and edit to create an associated
a. Suspend pair task
b. Terminate pair on primary task
c. Terminate pair on secondary task
d. Establish pair with re-sync task
e. Name, and save each task as you create
it
Chapter 4. Planning for communication
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