User's Manual

hp StorageWorks File System Extender User Guide 93
NOTE: To replace an original medium with its duplicate, you should label the duplicate medium with the
original barcode, remove the original medium, and use the duplicate instead.
When a medium copy is first used in place of the original, a warning is written to the fse.log file as the
FSE implementation recognizes that the medium for the particular barcode has been switched.
Typically, when you decide to duplicate a medium, for example for storing backup copies off-site, the
original medium is full and all its medium volumes are closed. If the medium is not yet full and still has
open volumes that are almost full, it is recommended that you first close all such volumes (as described in
”Closing medium volumes” on page 106), and then start duplicating. This way you will not have to repeat
the duplicating procedure each time new data is migrated to the original medium.
If you are duplicating a medium that still has open volumes, the medium volumes are copied as is and are
left open on the target medium. Therefore, you have to repeat the duplication procedure every time new
data is migrated to the original medium in order to have an up-to-date medium copy. In such cases, you
can reuse the same target medium as described in ”Procedure for duplicating media” on page 93.
Note that while a medium duplication is in progress, no other job (migration or recall) can use the disk
buffer space that was allocated. The migration jobs are resumed when disk buffer space is freed, while
recall jobs fail after the specified timeout.
Procedure for duplicating media
Before you start duplicating an FSE medium, you must ensure that the media duplication prerequisites are
met. Note that the most common reasons for media duplication failures are shortage of the FSE disk buffer
space and mismatches in the medium characteristics.
Prerequisites
• A target medium, which will hold a copy of the original data, must be of the same type as the original
medium.
• The target medium must have sufficient capacity.
• There must be enough free disk space for the FSE disk buffer. The minimal required space is the native
FSE medium capacity multiplied by 2, as shown in the following examples:
• The target medium should not contain any valid data or header such as a tar archive label or an
ECMA / ANSI label.
• The target medium should not be initialized.
• The target medium should not belong to any FSE media pool that is already assigned to an FSE
partition.
Normal duplication
When all duplication prerequisites are met, and the original and target media are prepared, you can
make a duplicate of the original medium using the following command:
If you do not want to monitor the medium duplication progress, specify the --no-monitor option as
shown in the command syntax above. Otherwise, the duplication progress will be reported to the standard
output.
LTO 1 : 100 GB * 2 = 200 GB
LTO 2 : 200 GB * 2 = 400 GB
LTO 3 : 400 GB * 2 = 800 GB
fsemedium --duplicate SourceBarcode TargetBarcode [--no-monitor]