Use the FlashCopy® mappings
Used by
a VDisk panel in the SAN Volume Controller Console to
display details about a selected FlashCopy mapping
associated with the selected virtual disk (VDisk).
Attributes
- Select
- Allows you to select the FlashCopy mapping
to use to
perform an action from the task list.
Note: Only one row can be selected
at a time.
- Name
- Displays
the name of the FlashCopy mapping.
- State
- Displays the current state of the FlashCopy mapping.
The following values are possible:
- 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 stopping.
- Stopped
- Indicates that the mapping has been stopped because either you
issued a command or an input/output (I/O) error 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 in this FlashCopy mapping.
- Target VDisk
- Displays the name of
the target virtual disk in this FlashCopy mapping.
- FC Group
- Displays the name of the FlashCopy consistency group
that contains this FlashCopy mapping.
- Progress (%)
- Displays the progress
of the copy operation shown as a completion
percentage 0% - 100%.
- 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
value selected can be the number 1 - 100 to indicate the copy rate
(a higher number indicates a faster copy rate) or NOCOPY,
which disables the copy process.
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.
- Automatically Delete
- Displays
whether a FlashCopy mapping will be
deleted when it is done copying. The following values are possible:
- Enabled
- Indicates the cluster supports the automatic
deletion of FlashCopy mapping when it is done copying.
- Disabled
- Indicates
the cluster supports the automatic deletion
of FlashCopy mapping when it is done copying;
however, the function is turned off.
- Not Supported
- Indicates that the cluster does not have
the capability to support
the automatic deletion of FlashCopy mapping.
- Incremental
- Displays
whether this FlashCopy is incremental.
The following values are possible:
- Yes
- Indicates
that only data changed since the last FlashCopy process
on the source and target VDisk will be copied.
- No
- Indicates that the entire VDisk will be copied during
a FlashCopy process.
Actions
You
can initiate the following actions from this panel:
- Create
a Mapping
- Modify a Mapping
- Delete a Mapping
- Prepare
a Mapping
- Start a Mapping
- Stop a Mapping
- View
FC Mappings in Dependency Order
- Go
- Click this button after selecting a task from the task
list. Clicking Go launches
the panel for the task that you selected.
- Refresh
- Click this button to refresh the table with changed values.