Object descriptors
A NetBackup XBSA object has a BSA_ObjectDescriptor, that contains cataloging information and optional application-specific object metadata. Cataloging information is capable of interpretation and searching by the NetBackup XBSA interface. Application-specific object metadata is not interpretable by the NetBackup XBSA interface but it can be retrieved and interpreted by an application. Using an object's objectName or its assigned copyId identifier, the corresponding BSA_ObjectDescriptor and object data can be retrieved through the NetBackup XBSA interface.
A BSA_ObjectDescriptor consists of a collection of object attributes. The basic data types used for XBSA object attributes are:
Fixed-length character strings
Hierarchical character strings (with a specified delimiter, and a length limit on the overall string)
Enumerations
Integers (with a specified range limit)
Date-time (in a standard C TM structure) format and precision; for example, yyyymmddhhmm)
The attributes are shown in the following table:
Table: BSA_ObjectDescriptor Attributes
Attribute | Data Type | Searchable |
|---|---|---|
objectOwner | (consisting of two parts) | Yes |
bsa_ObjectOwner | [fixed-length character string] | |
app_ObjectOwner | [hierarchical character string] | |
objectName | (consisting of two parts) | Yes |
objectSpaceName | [fixed-length character string] | |
pathName | [hierarchical character string] | |
createTime | [date-time] | Yes |
copyType | [enumeration] | Yes |
copyId | 64-bit unsigned integer | No |
restoreOrder | 64-bit unsigned integer | No |
resourceType | [fixed-length character string] | No |
objectType | [enumeration] | Yes |
objectStatus | [enumeration] | Yes |
objectDescription | [fixed-length character string] | No |
estimatedSize | [64-bit unsigned integer] | No |
objectInfo | [fixed-length byte string] | No |
Each NetBackup XBSA object is a copy of certain application object(s):
To preserve the semantics of the use of each copy within the BSA_ObjectDescriptor, each NetBackup XBSA object has a copyType of either backup or archive. The NetBackup XBSA interface recognizes the copyType so that the two types of objects can be managed differently and accessed separately.
Note:
It is up to the XBSA application to manage these types differently, as the NetBackup XBSA interface only keeps track of the type of the object.
Each NetBackup XBSA object also has an objectStatus of either most_recent or not_most_recent.
To capture an application object's type information, the corresponding NetBackup XBSA object can have a resourceType (for example, "filesystem") and a possible resource-specific BSA_ObjectType (for example, BSA_ObjectType_FILE).
An XBSA application can search for a NetBackup XBSA object within a certain search scope (for example, among objects in a certain objectSpaceName). It qualifies the search on the value of the appropriate searchable attributes.
On the other hand, non-searchable, application-specific attributes can be provided by an XBSA application for storage in the BSA_ObjectDescriptor, but the NetBackup XBSA interface does not interpret these attributes. They are stored in the NetBackup XBSA object attributes objectInfo, resourceType, and objectDescription.
The objectInfo field defaults to a character string. It can also be used to store binary data by using the NBBSA_OBJINFO_LEN XBSA environment variable.
Through these descriptor attributes, application-specific metadata can be stored in the catalog. Then, this metadata can be efficiently retrieved without retrieving the actual object data that is stored in the repository. An XBSA application can use these attributes to maintain inter-object relationships and dependencies. Some consideration should be given as to how much data is stored in the NetBackup Catalog. The amount of metadata that is stored with a few large objects can be larger than the amount that is stored for a million small objects.