HP XP Business Copy Software - Manual (Page 15)

Business Copy XP user guide for the XP128/XP1024 15
= 2,048 when number of CUs is equal to or less than 4
= 4,096 when number of CUs is equal to or more than 5
For example, if you create 10 pairs of OPEN-3 volumes and 20 pairs of OPEN-V (60 GB) volumes, the
total number of differential tables per pair, , is (1 x 10) + (7 x 20) = 150.
Because 150 is smaller than 2,048 (when number of CUs is equal to or less than 4) or 4,096 (when
number of CUs is equal to or more than 5), it meets the equation, , ensuring that 10 pairs of
OPEN-3 volumes and 20 pairs of OPEN-V (60 GB) volumes can be created.
• If an LU consists of more than one volume (when LUSE volumes are used):
The maximum number of pairs you can create is the largest number that meets the equation,
[ x (number of volumes that configure a LUSE volume)] is less than , where:
is total number of differential tables per pair
is number of differential tables in the disk array
= 2,048 when number of CUs is equal to or less than 4
= 4,096 when number of CUs is equal to or more than 5
For example, if you create 10 pairs of LUSE volumes consisting of three OPEN-3 volumes and 20 pairs
of LUSE volumes consisting of five OPEN-V (60 GB) volumes, [ x (number of volumes that configure
a LUSE volume)] is (1 x 3 x 10) + (7 x 5 x 20) = 730.
Because 730 is smaller than 2,048 (when number of CUs is equal to or less than 4) or 4,096 (when
number of CUs is equal to or more than 5), it meets the equation, [ x (number of volumes that
configure a LUSE volume)] is less than , ensuring that 10 pairs of OPEN-3 volumes and 20 pairs of
OPEN-V (60GB) volumes can be created.
The maximum number of pairs you can create is limited to the number of volumes installed.
Table 4 Number of pairs that can be created with volumes of each emulation type and capacity
Volume No. of
differential
tables per
pair needed
for controlling
the difference
between the
primary and
secondary volumes
No. of pairs
that can be
created
(If the volumes
of the same emulation
type and capacity are
used to create all
the pairs)
No. Emulation
Type
Capacity CUs is 4
or less
CUs is 5
or more
1 OPEN-3 Does not depend on capacity 1 2,047 4,095
2 OPEN-8 Does not depend on capacity 1 2,047 4,095
3 OPEN-9 Does not depend on capacity 1 2,047 4,095
4 OPEN-E 7.2 GB or less 1 2,047 4,095
5 7.3 GB or more 2 1,024 2,048
6 OPEN-L 7.2 GB or less 1 2,047 4,095
7 7.3 GB – 14.4 GB 2 1,024 2,048
8 14.5 GB – 21.6 GB 3 682 1,365
9 21.7 GB – 28.9 GB 4 512 1,024
10 29.0 GB or more 5 409 819
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