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Figure 6-11 TrueCopy Async suspension condition
TrueCopy/TrueCopy Async and Universal Replicator/global-active
device fence level settings
TrueCopy volume pairs are assigned a fence level for write I/Os to ensure
mirroring consistency of critical volumes. When the secondary volume takes
over from the primary volume, the takeover action is determined according to
the pair status and fence level of the corresponding secondary volume.
6-9 Relationship between TrueCopy pair statuses and fence levels on page
shows the relationship between TrueCopy pair statuses and fence levels.
The fence level for TrueCopy is Data, Status, Never. The fence level for
TrueCopy Async and Universal Replicator is always Async. The fence level for
global-active device is always Never.
•
Mirror consistency = Identity and sequence of data is assured via error
notification after an I/O completion.
•
Data consistency = Sequence of data is assured in I/O order based on
host.
6-30
Data replication operations with CCI
Command Control Interface User and Reference Guide
Summary of Contents for HUS VM
Page 10: ...x Command Control Interface User and Reference Guide ...
Page 18: ...xviii Preface Command Control Interface User and Reference Guide ...
Page 78: ...2 50 CCI software environment Command Control Interface User and Reference Guide ...
Page 154: ...4 8 Starting up CCI Command Control Interface User and Reference Guide ...
Page 191: ...Provisioning operations with CCI 5 37 Command Control Interface User and Reference Guide ...
Page 280: ...6 56 Data replication operations with CCI Command Control Interface User and Reference Guide ...
Page 286: ...6 62 Data replication operations with CCI Command Control Interface User and Reference Guide ...
Page 302: ...7 16 Data protection operations with CCI Command Control Interface User and Reference Guide ...
Page 324: ...8 22 Examples of using CCI commands Command Control Interface User and Reference Guide ...
Page 524: ...9 200 Troubleshooting Command Control Interface User and Reference Guide ...
Page 529: ...Command Control Interface User and Reference Guide ...