Use the REMOVABLEFILE device class for removable media
devices that are attached as local, removable file systems.
Privilege class
To issue this command, you
must have system privilege or unrestricted storage privilege.
Syntax
>>-DEFine DEVclass--device_class_name--------------------------->
>--LIBRary--=--library_name--DEVType--=--REMOVABLEfile---------->
.-MAXCAPacity--=--space_remaining-.
>--+---------------------------------+-------------------------->
'-MAXCAPacity--=--size------------'
.-MOUNTRetention--=--60------. .-MOUNTWait--=--60------.
>--+----------------------------+--+-----------------------+---->
'-MOUNTRetention--=--minutes-' '-MOUNTWait--=--minutes-'
.-MOUNTLimit--=--DRIVES-----.
>--+---------------------------+-------------------------------><
'-MOUNTLimit--=--+-DRIVES-+-'
+-number-+
'-0------'
Parameters
- device_class_name (Required)
- Specifies the name of the device class to be defined. The maximum
length of the device class name is 30 characters.
- LIBRary (Required)
- Specifies the name of the defined library object that contains
the removable media drives used by this device class. For information
about defining a library object, see the DEFINE LIBRARY command.
- DEVType=REMOVABLEfile (Required)
- Specifies that the REMOVABLEFILE device type
is assigned to the device class. REMOVABLEFILE indicates that the
volumes for this device class are files on local, removable media.
Volumes
in a device class with device type REMOVABLEFILE are sequential access
volumes.
- MAXCAPacity
- Specifies the maximum size of any volumes that are defined to
a storage pool categorized by this device class. This parameter is
optional.
The
MAXCAPACITY parameter must be set at less value than the capacity
of the media. For CD media, the maximum capacity can be no greater
than 650 MB.
Because the
server opens only one file per physical removable medium, specify
a capacity that enables one file to make full use of your media capacity.
- space_remaining
- The default maximum capacity is the space that remains on the
media after it is first used.
- size
- You must specify this value as an integer followed by K (kilobytes), M (megabytes), G (gigabytes),
or T (terabytes).
For example, MAXCAPACITY=5M specifies that the
maximum capacity for a volume in this device class is 5 MB. The smallest
value that is allowed is 1 MB (that is, MAXCAPACITY=1M).
- MOUNTRetention
- Specifies the number of minutes that an idle sequential access
volume is retained before it is dismounted. This parameter is optional.
The default value is 60 minutes. You can specify a number 0 - 9999.
This parameter can improve response time for sequential
access media mounts by leaving previously mounted volumes online.
Note: For
environments in which devices are shared across storage applications,
the MOUNTRETENTION setting must be carefully
considered. This parameter determines how long an idle volume remains
in a drive. Some media managers do not dismount an allocated drive
to satisfy pending requests. You might need to tune this parameter
to satisfy competing mount requests while maintaining optimal system
performance. Typically, problems arise more frequently when the MOUNTRETENTION parameter
is set to a value that is too small, for example, zero.
- MOUNTWait
- Specifies the maximum number of minutes the server waits for an
operator to respond to a request to either mount a volume in a drive
in a manual library or check in a volume to be mounted in an automated
library. This parameter is optional. If the mount request is not satisfied
within the specified amount of time, the mount request is canceled.
The default value is 60 minutes. You can specify a number 0 - 9999.
- MOUNTLimit
- Specifies the maximum number of sequential access volumes that
can be simultaneously mounted for the device class. This parameter
is optional. The default is DRIVES. You can specify a number 0 - 4096.
If you plan to use the simultaneous-write function, ensure
that sufficient drives are available for the write operation. If the
number of drives needed for a simultaneous-write operation is greater
than the value of the MOUNTLIMIT parameter for
a device class, the transaction fails.
The following are possible
values:
- DRIVES
- Specifies that every time a mount point is allocated, the number
of drives that are defined and online in the library is used to calculate
the true value.
Note: For EXTERNAL library types, do not specify DRIVES for the
MOUNTLIMIT value. Specify the number of drives for the library as
the MOUNTLIMIT value.
- number
- Specifies the maximum number of drives in this device class that
are used concurrently by the server. This value must never exceed
the number of drives that are defined and online in the library that
services this device class.
- 0 (zero)
- Specifies that no new transactions can gain access to the storage
pool. Any current transactions continue and complete, but new transactions
are terminated.