Connectors
A controller contains one or more connectors (channels or ports) to which you can attach disks. A connector is externally accessible for attaching an enclosure (with external disks) to the system. A connector may also be attached to the system's backplane (for internal disks). The controller's connectors are displayed by expanding the controller object in the tree view.
Channel Redundancy and Thermal Shutdown
It is possible to create a virtual disk that uses physical disks that are attached to different controller channels. The physical disks may reside in an external enclosure or the backplane (internal enclosure). If the virtual disk is maintaining redundant data on different channels, then the virtual disk is channel redundant. Channel redundancy means that if one of the channels fails, data is not lost because redundant data resides on another channel.
Channel redundancy might also be used for disks that reside in enclosures subject to thermal shutdown. Should the enclosure attached to one of the channels turn off, redundant data is maintained on the other channel.
Channel redundancy is implemented by selecting physical disks on different channels when using the Create Virtual Disk Advanced Wizard.
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NOTE: Channel redundancy only applies to controllers that have more than one channel and that attach to an external disk enclosure. |
Related Information:
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SMART Thermal Shutdown |
Channel Redundancy on PERC 4/DC, 4e/DC, 4/Di, and 4e/Di Controllers
The following considerations apply when creating a channel-redundant virtual disk on these controllers:
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It is recommended that you use a RAID 10 or RAID 50 when implementing channel redundancy on the PERC 4/DC, 4e/DC, 4/Di, and 4e/Di controllers. |
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If one of the channels (or enclosure) fails, you can no longer maintain I/O operations on any of the channels included in the channel redundant configuration even though data has not been lost. To restore I/O, do one of the following: |
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Fix the failed channel and reboot the system. |
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Reboot the system. This restores I/O on the channels that have not encountered a failure. The virtual disks on these channels are in a degraded state. |
Creating a Channel-redundant Virtual Disk
The following instructions describe creating a virtual disk that uses channel redundancy.
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NOTE: Channel redundancy only applies to controllers that have more than one channel and that attach to an external disk enclosure. |
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Launch the Create Virtual Disk Advanced Wizard by doing the following: |
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Complete Create Virtual Disk Advanced Wizard (Step 1 of 4). This portion of the Create Virtual Disk Advanced Wizard asks you to select a RAID level. When creating a channel-redundant virtual disk, it is recommended that you select the following RAID levels. |
Recommended RAID Levels:
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PERC 4/DC, 4e/DC, 4/Di, and 4e/Di Controllers—It is recommended that you only use RAID 10 or RAID 50. |
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Complete Create Virtual Disk Advanced Wizard (Step 2 of 4). In this step, you select the channels and the disks to be used by the virtual disk. The selections you make determine whether or not the virtual disk is channel-redundant. |
There are specific RAID level and configuration requirements for implementing channel redundancy. You must select the same number of physical disks on each channel that you use. For information on the number of physical disks that can be used for different RAID levels, see Number of Physical Disks per Virtual Disk. For information on controller-specific implementations of the RAID levels, see Controller-supported RAID Levels.
To complete Create Virtual Disk Advanced Wizard (Step 2 of 4), see Physical disk Selection for Channel-redundant Virtual Disks on PERC 4/DC, 4e/DC, 4/Di, and 4e/Di Controllers depending on the type of the controller.
Physical disk Selection for Channel-redundant Virtual Disks on PERC 4/DC, 4e/DC, 4/Di, and 4e/Di Controllers
The following sections describe creating a channel-redundant virtual disk using RAID 10 or RAID 50 on a PERC 4/DC, 4e/DC, 4/Di, or 4e/Di, controllers.
RAID 10
RAID 50
Connector Health
This screen displays the status of the connector and the components attached to the connector.
Connector Status
Component status is indicated by the severity. A component with a Warning or Critical/Failure status requires immediate attention to avoid data loss if possible. A component's status may indicate the combined status of the component and its lower-level objects. For more information, see Determining the Health Status for Storage Components.
It may be useful to review the Alert Log for events indicating why a component has a Warning or Critical status. For additional troubleshooting information, see Troubleshooting.
Connector Information
For information on the connector, see the following topics:
Connector Components
For information on attached components, see the following topic:
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Enclosures and Backplanes |
Connector Properties and Tasks
Use this window to view information about the connector and execute connector tasks.
Connector Properties
The connector properties can vary depending on the model of the controller. Connector properties may include:
Connector Tasks: Rescan Connector
Does my controller support this feature? See Supported Features.
On a SCSI controller, this task rescans the controller connectors to verify the currently connected devices or to recognize new devices that have been added to the connectors. Performing a rescan on a connector is similar to performing a rescan on the controller. For information on scheduling a rescan, see Rescan to Update Storage Configuration Changes.
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NOTE: Rescan is not supported on non-RAID SCSI controllers. You must reboot the system before Storage Management can see configuration changes on non-RAID SCSI controllers. Otherwise, configuration changes are not reflected in the Storage Management graphical user interface (GUI). |
To rescan a controller connector:
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Expand the Storage tree object to display the controller objects. |
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Expand a controller object. |
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Select a Connector object. |
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Select the Information/Configuration subtab. |
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Select Rescan from the Available Tasks drop-down menu. |
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Click Execute. |
Connector Components
For information on attached components, see the following topic:
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Enclosure and Backplane Properties and Tasks |
Logical Connector Properties and Tasks
Use this window to view information about the logical connector (connector in redundant path mode) and to execute connector tasks.
Logical Connector Properties
The connector properties can vary depending on the model of the controller. Connector properties may include:
Path Health
The path health of the connectors is represented as normal, warning, or critical. The possible values are displayed as Available, Degraded, or Failed.
If the enclosure health is displayed as degraded and further investigation shows all enclosure components (EMMs, Fans, Physical Disks, Power Supplies, and Temperature) to be in normal condition, select the Information/Configuration subtab of the enclosure to view details of the Path Failure.
Clearing the Redundant Path View
If you do not want the redundant path view, physically disconnect the connector port from the enclosure and reboot the system. After the system reboots, the user interface still displays the Logical Connector, but in a critical state. If you are certain you do not want the redundant path mode, select Clear Redundant Path view from the Controller Tasks.
Selecting this option clears the redundant path view and the connectors are represented on the user interface as Connector 0 and Connector 1.
Related Tasks
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Redundant Path Configuration |
Logical Connector Components
For information on attached components, see the following topic:
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Enclosure and Backplane Properties and Tasks |