DEFINE DEVCLASS (Define a CENTERA device class)

Use the CENTERA device class when you are using EMC Centera storage devices. The CENTERA device type uses files as volumes to store data sequentially. It is similar to the FILE device class.

Privilege class

To issue this command, you must have system privilege or unrestricted storage privilege.

Syntax

Notes:

¹ For each Centera device class, you must specify one or more IP addresses. However, a Pool Entry Authorization (PEA) file name and path are optional, and up to one PEA file specification can follow the IP addresses. Use the "?" character to separate the PEA file name and path from the IP addresses.

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.

DEVType=CENTERA (Required)

Specifies that the Centera device type is assigned to this device class. All volumes that belong to a storage pool that is defined to this device class are logical volumes that are a form of sequential access media.

HLAddress

Specifies one ore more IP addresses for the Centera storage device and, optionally, the name and path of one Pool Entry Authorization (PEA) file. Specify the IP addresses with the dotted decimal format (for example, 9.10.111.222). A Centera device might have multiple IP addresses. If multiple IP addresses are specified, then the store or retrieve operation attempts a connection by using each IP address that is specified until a valid address is found.

AIX operating systems The PEA file name and path name are case-sensitive.

If you append the name and path of a PEA file, ensure that the file is stored in a directory on the system that runs the server. Separate the PEA file name and path from the IP address with the "?" character, for example: Windows operating systems

   HLADDRESS=9.10.111.222,9.10.111.223?c:\controlFiles\TSM.PEA

   HLADDRESS=9.10.111.222,9.10.111.223?/user/ControlFiles/TSM.PEA

Specify only one PEA file name and path for each device class definition. If you specify two different Centera device classes that point to the same Centera storage device and if the device class definitions contain different PEA file names and paths, the server uses the PEA file that is specified in the device class HLADDRESS parameter that was first used to open the Centera storage device.

Tips:

The server does not include a PEA file during installation. If you do not create a PEA file, the server uses the Centera default profile, which can allow applications to read, write, delete, purge, and query data on a Centera storage device. To provide tighter control, create a PEA file with the command-line interface that is provided by EMC Centera. For details about Centera authentication and authorization, refer to the EMC Centera Programmer's Guide.
You can also specify the PEA file name and path in an environment variable with the syntax CENTERA_PEA_LOCATION=filePath_ fileName. The PEA file name and path that is specified with this environment variable apply to all Centera clusters. If you use this variable, you do not have to specify the PEA file name and path with the HLADDRESS parameter.

MINCAPacity

Specifies the minimum size for Centera volumes that are assigned to a storage pool in this device class. This value represents the minimum amount of data that is stored on a Centera volume before the server marks it full. Centera volumes continue to accept data until the minimum amount of data is stored. This parameter is optional.

Specify this value as an integer followed by K (kilobytes), M (megabytes), G (gigabytes), or T (terabytes). The default value is 100 MB (MINCAPACITY=100M). The minimum value that is allowed is 1 MB (MINCAPACITY=1M). The maximum value that is allowed is 128 GB (MINCAPACITY=128G).

MOUNTLimit

Specifies the maximum number of files that can be simultaneously open for input and output. The default value is 1. This parameter is optional. You can specify any number from 0 or greater; however, the sum of all mount limit values for all device classes that are assigned to the same Centera device must not exceed the maximum number of sessions that are allowed by Centera.