Hitachi ShadowImage for z/OS user guide (HIT9503-96007, October 2007)

ShadowImage for z/OS user guide 115
The following figure shows the example of when 7 pairs are created with 3390-3 volumes, and 3 pairs are
created with 3390-L volumes (32,769 CYL).
Figure 61 Referential Example for Calculating the Number of Pairs
According to Figure 61, the total number of resources used per pair is calculated as:
Resources used for A - H = (3 + 1) + 1 + 1 + 1 + 1 + 1 + (9 x 3) + 9 + 9 = 54.
The conditions for the number of pairs you can create are:
Σ(α) ≤ (β) and Σ(γ) ≤ 32,768
In the case of the example shown in Figure 61, 54 ≤ 13,652 when additional shared memory is not
installed, 54 ≤ 30,718 when additional shared memory is installed. Since the example shown in Figure 61
meets the conditions shown above, you can create all the pairs in Figure 61.
Installing and Uninstalling Compatible Mirroring for IBM FlashCopy Version2
This sections describes how to install and uninstall FlashCopy Mirror Version 2.
Installing Compatible Mirroring for IBM FlashCopy Version2
This section describes how to install FlashCopy Mirror Version 2. The installing steps are different
depending on whether FlashCopy Mirror is installed or not. Note that you do not need to see step 2 and
step 3 if you do not have installed FlashCopy Mirror.
To install FlashCopy Mirror Version 2:
1. Check whether there is a need to install additional shared memory or not.
For details, please contact your HP account representative.