Use the Viewing dependant FlashCopy mappings for VDisk panel in the SAN Volume Controller Console to display FlashCopy mappings that have target VDisks that are dependent upon data held on the specified VDisk. This information can be used to determine whether a FlashCopy® mapping can be prepared.
Attributes
If no mappings are shown on the panel for the selected VDisk, the FlashCopy mapping can be prepared. If mappings are shown on the panel, the mappings must be in the stopped, idle, or copied state before the new FlashCopy mapping can be prepared.
The following attributes are displayed in the table:
- Name
- Displays the name of the FlashCopy mapping. Click a name to display the View FlashCopy Mappings Details panel for that mapping.
- State
- Displays the current state of the FlashCopy mapping. The following values are valid:
- Idle or Copied
- Indicates that the source and target VDisks act as independent VDisks even if a FlashCopy mapping exists between the two. Read and write caching is enabled for both the source and the target.
- Preparing
- Indicates that any changed write data for the source VDisk is flushed from the cache. Any read or write data for the target VDisk is discarded from the cache.
- Prepared
- Indicates that the mapping is ready to be started. While in this state, the target VDisk is offline.
- Copying
- Indicates that the copy is in progress.
- Stopping
- Indicates that the copy is in the stopping state.
- Stopped
- Indicates that the mapping has been stopped because either you issued a command or an input/output (I/O) error has occurred. The copy can be restarted by preparing and starting the mapping again.
- Suspended
- Indicates that the copy bitmap is unavailable. The copying resumes when the bitmap recovers.
- Source VDisk
- Displays the name of the source virtual disk for the FlashCopy mapping.
- Target VDisk
- Displays name of the target virtual disk for the FlashCopy mapping.
- FC Group
- Displays the name of the FlashCopy consistency group that is associated with this FlashCopy mapping.
- Partner
- Displays the name of the partner FlashCopy mapping associated
with this FlashCopy mapping. A partner FlashCopy mapping is a mapping
which consists of the same VDisk, but the source and target VDisks
are reversed. For example, if one mapping contains vdisk1 and vdisk2,
where vdisk1 is the source and vdisk2 is the target, then its partner
mapping consists of vdisk2 as the source and vdisk1 as the target.
- Progress (%)
- Displays the progress of the FlashCopy operation if one is in process, shown as a completion percentage from 0% to 100%. If the state is Stopping, the displayed value represents the percentage complete of the process that stopped the copy.
- Cleaning Progress (%)
- Displays the progress of the FlashCopy mapping cleaning operation if one is in process. The value is shown as a completion percentage of 0% - 100%. The cleaning process must complete before the FlashCopy mapping moves to the stopping state.
- Copy Rate
- Displays the copy rate for this mapping. The selected value can be either a number from 1 - 100 to indicate the copy rate (a higher number indicates a faster copy rate) or NOCOPY, which disables the copy.
The following table shows the relationship of
the copy and cleaning rate value to the attempted number of grains
to be split per second. A grain is the unit of data represented by
a single bit.
Table 1. Relationship between the rate,
data rate and grains per second values| User-specified rate attribute value |
Data copied/sec |
256 KB grains/sec |
64 KB grains/sec |
|---|
| 1 - 10 |
128 KB |
0.5 |
2 |
| 11 - 20 |
256 KB |
1 |
4 |
| 21 - 30 |
512 KB |
2 |
8 |
| 31 - 40 |
1 MB |
4 |
16 |
| 41 - 50 |
2 MB |
8 |
32 |
| 51 - 60 |
4 MB |
16 |
64 |
| 61 - 70 |
8 MB |
32 |
128 |
| 71 - 80 |
16 MB |
64 |
256 |
| 81 - 90 |
32 MB |
128 |
512 |
| 91 - 100 |
64 MB |
256 |
1024 |
The data copied per second and the
grains per second numbers represent standards that the SAN Volume
Controller tries to achieve. The SAN Volume Controller is unable to
achieve these standards if insufficient bandwidth is available from
the nodes to the physical disks that make up the managed disks (MDisks)
after taking into account the requirements of foreground I/O. If this
situation occurs, background copy I/O contends for resources on an
equal basis with I/O that arrives from hosts. Both tend to see an
increase in latency and consequential reduction in throughput with
respect to the situation had the bandwidth not been limited.
- Restore
- Indicates whether the FlashCopy mapping is being used to restore
data. The following values are possible:
- Yes
- Indicates that the FlashCopy mapping is restoring
data to the target VDisk, which is an active source VDisk of another
FlashCopy mapping.
- No
- Indicates that either the restore option was not specified when
the FlashCopy mappings was prepared or started or that the conditions
that required the restore option to be specified no longer exist.
- Automatically Delete
- Displays whether the FlashCopy mapping is deleted after the copy completes. The following values are possible:
- Enabled
- Indicates that the cluster supports the automatic deletion of the FlashCopy mapping after the copy completes.
- Disabled
- Indicates that the cluster supports the automatic deletion of the FlashCopy mapping after the copy completes. This function is currently turned off.
- Not Supported
- Indicates that the cluster does not have the capability to support the automatic deletion of the FlashCopy mapping.
Actions
The following action is available:
- Refresh
- Click this button to update the list of mappings.