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Example 4—Decision support using the instant full snapshot feature and the vxibc utility

1. On the Secondary, prepare the volumes for which you want to create instant snapshots using the command:

   # vxsnap -g hrdg prepare hr_dv01

   # vxsnap -g hrdg prepare hr_dv02

   This operation needs to be performed only for the first time you perform the snapshot operation.

2. On the Secondary, create snapshot volumes of the same size as the original volumes and with an appropriate prefix:

   # vxassist -g hrdg make dss-hr_dv01 volume_length

   # vxassist -g hrdg make dss-hr_dv02 volume_length

   where volume_length is the length of the original volumes.

3. On the Secondary, prepare the snapshot volumes for which you want to create instant snapshots using the command:

   # vxsnap -g hrdg prepare dss-hr_dv01

   # vxsnap -g hrdg prepare dss-hr_dv02

4. On the Secondary, issue the following command:

   # vxibc -g hrdg regrecv dss_app hr_rvg [vxrvg -g hrdg -F -P dss \
   snapshot hr_rvg]

   The command vxrvg -g hrdg -F -P dss snapshot hr_rvg is run when the IBC message arrives on the Secondary and the command creates an instant full snapshot.

5. On the Primary, put the application that is using the Primary data volumes hr_dv01 and hr_dv02 into consistent state using the application specific method. For information on the consistent state, see step 2.
6. On the Primary, register the application name dss_app and send the IBC message using the following command:

   # vxibc -g hrdg regsend dss_app hr_rvg

7. On the Primary host, resume the application if it was suspended in step 5.

   If the RLINK is asynchronous and behind there may be a delay between the vxibc regsend and vxrvg snapshot command. During this delay, the application is running.

8. On the Secondary, use the snapshot data volumes dss-hr_dv01 and dss-hr_dv02 for running the DSS application, that is, for off-host processing.
9. When the application completes, reattach the snapshot plexes to the data volumes using the following command:

   # vxrvg -g hrdg snapback hr_rvg

   The reattach destroys the dss volumes and reattaches the snapshot plexes to their original volumes.