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1 primary site failure, Host – IBM DS6000 User Manual

Page 377

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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