Disks

The main screen for disks shows a list of all defined disks, as well as their used and free space and a set of options.

These options are:

• Disk audit. Equal to generating a disk audit job from the general audit section

• Datamover. Equal to generating a datamover job, which will lead to the definition of a new disk. See section Datamover for further detail

• Edit

Registering a disk, done with the button Create a new disk, is a non-reversible process, and most of its data turn out to be non-editable. Because of this, it is especially important to be careful when inserting the data, and to do a thorough review of the introduced parameters before finishing the disk registration.

Fields that define a disk are:

1. UNC path. Disk access. When referring to a logical unit, it is important that the disk has the necessary creation, reading and writing permissions granted, as well as those permissions on created folders.

2. Storage group, to which it is being assigned.

3. Label or disk name in the LIBSAFE system. This is editable.

4. Description. Editable and mandatory.

5. Size. It indicates the supposed size of the disk. It is completed with the unit box placed in the same line. It is recommended to write the real size of the disk for dedicated units, and whatever is granted in logical disks, when they are really from shared units (i.e.: network disks). Not editable.

6. Free space. It indicates the size of the free space. Not editable.

7. Priority. It indicates the priority with which its space will be used, within the storage group to which it belongs.

8. Allow more objects. Editable. It allows for disabling the use of the disk for the insertion of new objects.

9. Transparent storage. We must select Yes when the storage has access to the disk in Read-Only mode and we wish the content of all the preserved objects to be accessible by means of the Object Explorer.

Important: it is very important to understand that once the size and path of a disk is defined, they cannot be changed. Care must be taken in their definition. An implication of the impossibility to edit those values is that if a unit’s size increases (can be in a logical unit), it will not be possible to use this capacity directly, and it will be necessary to define an intermediate disk and use a datamover job to allow for the un-registration and re-registration of the updated disk.

Something to take into consideration when sizing the system is that, for storage security, LIBSAFE will keep a small percentage of the disk without use to avoid excessive fragmentation and possible loss of system performance, as well as to guarantee the real availability of space for new ingestions.

Note: Every object in LIBSAFE complies with the condition of being preserved completely (for each of its copies) in only one disk. This is mandatory, to comply with the OAIS requirement to be able to see and use an object by direct inspection of its storage location.