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 will be displayed 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. You may 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
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
➔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 deleted by highlighting the row in the device window and clicking the REMOVE MAP button.
19 ATTO Technology BridgeTools Installation and Operation Manual