HP XP P9000 Continuous Access Synchronous User Guide

• If a split or suspend operation is in progress when I/O processing on Cnt Ac-S or Cnt Ac-S Z
pairs begins, the split operation on the pairs is given priority. After the pair is split, then the
I/O processing begins.
• Data consistency cannot be ensured when all of the following conditions exist:
- A port is blocked.
- A split command is in progress.
- I/O processing begins.
In such a case, resynchronize the consistency group and then run the split command again.
Host access after suspension
You can specify settings for read/write access to the P-VOL/M-VOL and S-VOL/R-VOL in consistency
groups after pairs are suspended. These settings are specified using RAID Manager or Business
Continuity Manager.
• The RAID Manager settings for Cnt Ac-S are optional.
• The Business Continuity Manager settings for Cnt Ac-S Z are required.
The following tables show the effects of the settings on read and write access.
Cnt Ac-S Z M-VOLCnt Ac-S P-VOLSettingInterface
WriteReadWriteRead
NYNYWrite access prohibitedRAID Manager
YYYYNo option selected
NYNYWrite access prohibitedBusiness Continuity
Manager
YYYYWrite access permitted
Cnt Ac-S Z R-VOLCnt Ac-S S-VOLSettingInterface
WriteReadWriteRead
NNNYRead access permittedRAID Manager
YYYYRead/Write access permitted
NNNYNo option selected
NNNYWrite access prohibitedBusiness Continuity
Manager
YYYYWrite access permitted
30 Planning for Continuous Access Synchronous