Devices ii(7D)
NAME
ii - Instant Image control device
DESCRIPTION
The ii device is a control interface for Instant Image dev-
ices and controls the Instant Image module through the ioctl(2) interface.Instant Image is a point-in-time volume copy facility for
the Solaris operating environment that is administeredthrough the iiadm(1M) command. With Instant Image, you can
create an independent point-in-time copy of a volume or a
master volume-dependent point-in-time view. You can also
independently access the master and shadow volume for read and write operations. Instant Image also lets you update the shadow volume from the master volume or restore the master volume from the shadow. (Restore operations to volumes can be full or incremental). Instant Image supports fast volumere-synchronization, letting you create a new point-in-time
volume copy by updating the specified volume with only changed data. To create a shadow volume you need a: 1. Master volume to be shadowed. 2. Shadow volume where the copy will reside. This volume must be equal to or larger than the master volume. 3. Administrative bitmap volume or file for tracking differences between the shadow and master volumes. The administrative bitmap volume or file must be at least 24Kbytes in size and requires 8KBytes for each GByte (or part thereof) of master volume size, plus an additional 8KBytes overhead. For example,to shadow a 3GByte master volume, the administra-
tion volume must be 8KBytes + (3 * 8KBytes) =32KBytes in size. The Instant Image module uses services provided by the SDBCand SD_GEN modules. The SV module is required to present a
conventional block device interface to the storage productinterface of the Instant Image, SDBC and SD_GEN modules.
When a shadow operation is suspended or resumed, the administration volumes may be stored in permanent SDBC storage or loaded and saved to and from kernel memory. TheSunOS 5.11 Last change: 8 Jun 2007 1
Devices ii(7D)
ii_bitmap variable in the /kernel/drv/ii.conf configuration
file determines the administration volume storage type. Avalue of 0 indicates kernel memory, while a value of 1 indi-
cates permanent SDBC storage. If the system is part of a storage products cluster, use the 1 value (permanent storage), otherwise use kernel memory (0 value). FILESkernel/drv/ii 32- bit ELF kernel module (x86).
/kernel/drv/ii.conf Configuration file.
ATTRIBUTES
See attributes(5) for a description of the following attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Architecture | x86 ||_____________________________|_____________________________|
| Availability | SUNWiu ||_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
SEE ALSO
iiadm(1M), ioctl(2), attributes(5), sv(7D)
SunOS 5.11 Last change: 8 Jun 2007 2