IBM System storage DS6000 Series, Redbook

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Chapter 26. Global Mirror examples
353
Figure 26-2 Global Mirror configuration before unplanned primary failure
The production applications write to three primary volumes that are part of a Global Mirror
session.
26.4.1 Primary site failure
We simulate a primary site failure that may not be fatal to the storage disk subsystem.
Figure 26-3 Unplanned primary site failure
In our testing environment, we simulated a primary site failure with a CGROUP FREEZE
command to both primary LSSs. See Figure 26-3 and Example 26-16 on page 354.
A more strict primary volume failure may be simulated through a V OFFLINE,FORCE to the
Global Copy primary volumes. This will also fail the application I/Os to the volumes. If you use
this testing procedure, do not forget to reply to the corresponding WTOR for each V
OFFLINE,FORCE.
Global Copy
Primary
Primary
A
2D01
Primary
Primary
A
2D00
Primary
A
2C00
Host
FICON
Local site
Primary
Primary
A
3F01
Primary
Primary
A
3F00
Tertiary
C
3E00
Primary
Primary
A
3D01
Primary
Primary
A
3D00
Secondary
B
3C00
73081
27131
I/O
a
ct
iv
ity
FlashCopy
FCP links
Remote site
FlashCopy
Global Copy
Primary
Primary
A
3F01
Primary
Primary
A
3F00
Tertiary
C
3E00
Primary
Primary
A
3D01
Primary
Primary
A
3D00
Secondary
B
3C00
Host
Remote site
Primary
Primary
A
2D01
Primary
Primary
A
2D00
Primary
A
2C00
Local site