CP 3100 Operation
Archiving and Migrating
99
Archiving and Migrating
By default the CP 3100 copies (archives) data from a virtual cartridge to a physical tape. This
ensures that there is a permanent form of storage for your data. After an archive is complete, the
data in the virtual cartridge remains on the hard drive. This enables restore operations to be per-
formed quickly, at disk speed.
A Migrate action occurs when the CP 3100 needs to free space on the hard drive to store more data
onto a virtual cartridge. A Least Recently Used algorithm determines which virtual cartridge data to
remove from the hard drive. In this way, the CP 3100 can store data continually and never become
“full.” Data does not migrate until the CP 3100 needs to do so.
You may want some data to remain stored on the hard drive for a longer period of time. You can use
the
Do Not Archive
and
Do Not Migrate
options to hold data within an individual virtual car-
tridge as long as desired. You can also prevent any virtual cartridge data from being removed from
the CP 3100, though this is not recommended.
As discussed under “Viewing Device Properties” on page 59, you can automatically archive data to
a physical tape always or choose to never perform an archive from any virtual cartridge. The same
choices are available for Migrate. There is a consequence for choosing
Do Not Archive
or
Do
Not Migrate
.
•
If you choose
Do Not Archive
to never perform an archive, your data will never be perma-
nently stored on a removable medium that you can safely store away. In addition, the
CP 3100 hard drive(s) will eventually become full and you will not be able to store data onto
the CP 3100. Consequently, you will not be able to perform backups.
•
If you choose to archive but choose
Do Not Migrate
to never migrate, you can store your
data onto physical tapes; however, the CP 3100 hard drive(s) will eventually become full and
you will not be able to store data onto the CP 3100. Therefore, you will not be able to per-
form backups.
To ensure that certain data is stored permanently on the CP 3100, choose the appropriate option
with a particular virtual cartridge. The section “Configuring a Virtual Tape Cartridge” on page 64
describes the options to archive/not archive and migrate/not migrate a particular virtual cartridge.
Checking the
Do Not Migrate
box allows data in the virtual cartridge to be archived to physical
tape, but ensures that the data stays on the CP 3100 hard drive until you decide it is time to migrate
the data (see “Manually Performing a Migrate Operation” on page 67). You must still ensure that
the host backup software does not overwrite the data on the virtual cartridge by performing erase,
tape labeling, or backup operations to the virtual cartridge.
