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ATTO Technology BridgeTools Installation and Operation Manual
4.8 Mapping panel
The mapping panel assigns LUNs, maps SCSI devices to FibreChannel ports and troubleshoots FC ports
and connected SCSI devices. The number of ports available depends on the particular model of the
FibreBridge.
In order for a host computer to communicate to a SCSI
storage device connected to the FibreBridge, the host must
be able to identify the storage device (target). To the host,
each SCSI target is identified as a Fibre Channel ID and a
LUN (ex. ID 0 LUN 1). The Fibre Channel ID is the actual
ID of the bridge’s Fibre Channel port (set on the Fibre
Channel Panel). The LUN can be set to virtually any value
using this panel.
The FibreBridge moves data between a Fibre Channel port
and a connected SCSI storage device (target). The best way
to achieve maximum throughput to the SCSI devices is to
balance the connected SCSI devices among the Fibre
Channel and SCSI ports. This is done by mapping, or
assigning each SCSI device to any of the Fibre Channel
ports.
When you first open the Mapping panel after launching
BridgeTools, the device window will be empty. Clicking the
SCAN
button at the bottom of the panel will instruct the
bridge to detect all of the connected SCSI targets.
Information for each SCSI target found wil l be d isplay ed in
a row within the window: the make and model of the device,
the SCSI bus or port of the bridge the device is connected to,
and the Target ID and LUN the device is physically set to.
Each detected SCSI target will be assigned a LUN and will
be mapped to the Fibre Channel port(s).
The port assignment and LUN value can be changed by
simply clicking in the cell of the table. A pull down list will
appear showing the available choices. It is important to
remember that every target on each Fibre port must be
assigned a unique ID. Y ou m ay have a LUN 0 on Fibre port
0 and a LUN 0 on Fibre port 1, but an error will occur if
there are multiple LUN 0s on the same Fibre port.
The Fibre Channel port(s) of the FibreBridge will also be
displayed in the device window. Each of these ports is also
considered a target device for Serverless Backup
applications or when BridgeTools is communicating with
the bridge over the in-band connection. Because of this, the
LUNs assigned to the SCSI targets must be different than
the LUN assigned to the bridge port itself. The Fibre
Channel Port LUN can be assigned using the Fibre Channel
panel within BridgeTools.
The device window also contains an ACTION for each
SCSI target detected to set a target to either Online or
Offline. The target must be set to Online for the bridge to
pass through SCSI commands. If the target is set to Offline,
SCSI commands to that target will be rejected. Offline can
be used for balancing hours of use between tape drives.
➔
The read-only STATUS column in the
device window is used to report the status
of each mapped SCSI target.
➔
ONLINE indicates the device is online and
is able to accept SCSI commands.
➔
UNAVAILABLE indicates that no device
is present at a particular mapping.
➔
OFFLINE indicates that a device is not
able to accept SCSI commands
➔
GOING OFFLINE indicates that a device
was set to Offline in the Action column, but
queued commands to the device have not
yet completed.
New SCSI devices will automatically be assigned a LUN
and mapped to one of the Fibre Channel ports but will be set
to OFFLINE. The ACTION for each target device must be
set to ONLINE before a host computer will be able to access
it.
Once all of the mappings and actions have been completed,
the
APPLY
button must be selected to make the changes
take effect. If there is an error with the mappings (for
example, two targets were assigned the same LUN on the
same Fibre port), BridgeTools will display a warning in the
message box at the bottom of the page. Unlike modifying
the other parameters using BridgeTools, mapping changes
take affect immediately after hitting APPLY. However, the
changes will not remain after a power cycle unless they are
saved using the Save/Restore panel.
The Mapping Panel also contains features to add a map or
remove a map. Clicking the
ADD MAP
button will add a
blank row to the device window. This can be useful for
mapping devices that will be connected to the FibreBridge
in the future. The future device can be mapped by filling in
the Fibre Port and Fibre LUN mapping fields. In addition,
information for the intended SCSI Bus, SCSI Target and
SCSI LUN fields must also be entered. All information must
be filled in or an error message will appear when the APPLY
button is selected.
The mapping for any device can be de leted by highlighting
the row in the device window and clicking the
REMOVE
MAP
button.