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HP StorageWorks XP Remote Web Console Software User Manual

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Differences Between IBM FlashCopy and Compatible Mirroring for IBM FlashCopy

Version 2

Table 60

Differences Between IBM FlashCopy and Compatible Mirroring for IBM FlashCopy Version 2

No.

Compared item

IBM FlashCopy

FlashCopy Mirror Version 2

1

Read access to the

area not specified as

the copy range in the

copy target in

NOCOPY mode

The data on the tracks subject to read

operation are not copied from the copy

source to the copy target.

The data on the tracks subject to read

operation are copied from the copy

source to the copy target.

2

Status of the pairs

when On-demand

copy is processed

Pairs are withdrawn automatically

when all the copy operations processed

by On-demand copy are completed.

Pairs are maintained even when all the

copy operations processed by

On-demand copy are completed.

3

Sharing T-VOL with

other copy solutions

Pairs that include the following shared

volume can be created:

PPRC pair that includes a volume

used as FlashCopy S-VOL as well

as PPRC T-VOL

PPRC pair that includes a volume

used as FlashCopy T-VOL as well as

PPRC S-VOL

PPRC pair that includes a volume

used as FlashCopy T-VOL as well as

PPRC T-VOL

Not supported.

Message “ANTF0353E” appears.

4

Number of multiple

relationships

Up to 12 pairs can be created per

extent (the smallest unit: track).

Up to 16 pairs can be created per

extent (the smallest unit: track).

5

Maximum number of

pairs that can be

created per volume

951 pairs (for 3390-3)
2,719 pairs (for 3390-9 when the

number of available cylinders are

10,017)
7,615 pairs (for 3390-L when the

number of available cylinders are

28,356)
8,839 pairs (for 3390-L when the

number of available cylinders are

32,760)

1,000 pairs (for all volume types)

6

FCWITHDR command
(DDSW = NO,

XTNTLST parameter

specified)

The command withdraws the copy

targets of pairs existing within the

extents specified as the target, provided

that:

When the copy target of the pair is

only partly included in the extent

specified as the target, only the

area that is included in the extent is

withdrawn.

When only the central part of the

copy target of the pair is included

in the extent specified as the target,

only the area that is included is

withdrawn. The remaining area of

the pair is divided up.

The command withdraws the copy

targets of pairs existing within the

extents specified as the target. When

the copy target of the pair is only partly

included in the extent specified as the

target, the command does not

withdraw the pair.

7

REMOVEFCPY
(ICKDSF CONTROL

command)

The command will finish normally. Pairs

will not be deleted.

Not supported. The command will

finish abnormally. Pairs will not be

deleted.