–Release all pairs in a journal group. See section Deleting Data Volumes from a Mirror (Ending a copy operation) for a description of the Delete
•Group operations at the secondary storage system
–Split (suspend pair) all pairs in a journal group. See section Splitting a Mirror (Suspending a copy operation) for a description of the Suspend
–Release (delete pair) all pairs in a journal group regardless of their consistency status. See section Deleting Data Volumes from a Mirror (Ending a copy operation) for a description of the Delete
Read and Write I/O Operations During URz Operations
When a primary storage system receives a read I/O for a URz primary data volume, the primary storage system performs the read from the primary data volume. If the read fails, the redundancy provided by
When a primary storage system receives a write I/O for the primary data volume with PAIR status, the primary storage system performs the update copy operation, as well as writing to the primary data volume.
The primary storage system completes the primary data volume write operations independently of the update copy operations at the secondary data volume. The secondary storage system updates the data in the secondary data volume according to the write sequence number of journal data. This will maintain the data consistency between the primary and secondary data volumes. If the primary data volume write operation fails, the primary storage system reports a unit check and does not create the journal data for this operation. If the update copy operation fails, the secondary storage system suspends either the affected pair or all URz pairs in the journal group, depending on the type of failure. When the suspended URz pair or journal group is resumed (Resume Pair), the primary storage system and secondary storage system negotiate the resynchronization of the pair(s). See section Suspend Types for further information on URz suspend types.
During normal URz operations, the secondary storage system does not allow URz secondary data volumes to be online (mounted), and therefore hosts cannot read from and write to secondary data volumes. The URz secondary data volume write enable option allows write access to a secondary data volume while the pair is split (see the next section). The secondary data volume write option can only be enabled when you split the pair from the primary storage system.
Chapter 3 Preparing for Universal Replicator z/OS Operations |
