Figure 27 R21 device in cascaded SRDF
Site B
Site A
SRDF Links
Production
host
Site C
R1
R21
R2
When the R1->R21->R2 SRDF relationship is established, no host has write access to
the R21 device.
Note
Diskless R21 devices are not supported on arrays running HYPERMAX OS.
R22 devices
R22 devices:
l
Have two R1 devices, only one of which is active at a time.
l
Are typically used in cascaded SRDF/Star and concurrent SRDF/Star solutions to
decrease the complexity and time required to complete failover and failback
operations.
l
Let you recover without removing old SRDF pairs and creating new ones.
Figure 28 R22 devices in cascaded and concurrent SRDF/Star
SRDF/S
Site A
SRDF/A
Site C
SRDF/S
Site B
Active
links
Host
Host
Site B
Site A
Site C
SRDF/A
SRDF/A
SRDF/A
Cascaded STAR
Concurrent STAR
Inactive
links
R22
R2
R11
R21
R11
R21
SRDF device states
An SRDF device’s state is determined by a combination of two views; host interface
view and SRDF view, as shown in the following image.
Remote replication solutions
SRDF device states
119
Summary of Contents for VMAX 100K
Page 1: ...EMC VMAX3 Family Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS REVISION 6 5 ...
Page 20: ...Preface 20 Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS ...
Page 46: ...VMAX3 with HYPERMAX OS 46 Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS ...
Page 72: ...Open systems features 72 Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS ...
Page 82: ...Provisioning 82 Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS ...
Page 158: ...Remote replication solutions 158 Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS ...
Page 186: ...Mainframe Error Reporting 186 Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS ...
Page 200: ...Licensing 200 Product Guide VMAX 100K VMAX 200K VMAX 400K with HYPERMAX OS ...