IBM DS6000 - Manual (Page 302)

278 IBM System Storage DS6000 Series: Copy Services with IBM System z
Figure 23-5 Dedicated and shared links
In Figure 23-5 an FCP port in the Master storage disk subsystem is used as Global Mirror link
to the other two Subordinate storage disk subsystems, and is also used as Global Copy link
to the secondary storage disk subsystem. Also, there are ports at the Subordinate storage
disk subsystem that are used as Global Mirror session link as well as Global Copy link.
If possible, a better configuration is the one shown in Figure 23-6. Again, from a performance
and throughput viewpoint, you would not need two Global Mirror links between the Master
and its Subordinate storage disk subsystems. Still, dedicated ports for Global Mirror control
communication between Master and Subordinate provides a maximum of responsiveness.
Primary
Primary
A
A
Primary
PENDING
Primary
Primary
Primary
Primary
A
B
Secondary
C
Tertiary
PENDING
01
Master
Primary
Primary
A
A
Primary
PENDING
Primary
Primary
Primary
Primary
A
B
Secondary
C
Tertiary
PENDING
01
Subordinate
Primary
Primary
A
A
Primary
PENDING
Primary
Primary
Primary
Primary
A
B
Secondary
C
Tertiary
PENDING
Network
01
Subordinate
Global Copy links
GM links
Global Copy links
Global Copy links
Remote site Local site