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Connectors

Dell OpenManage™ Server Administrator Storage Management User's Guide

  Channel Redundancy and Thermal Shutdown

  Channel Redundancy on PERC 3/DCL, 3/DC, 3/QC, 4/DC, 4e/DC, 4/Di, and 4e/Di Controllers

  Creating a Channel-redundant Virtual Disk

  Connector Health

  Connector Properties and Tasks

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 will not be 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 shut down, 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.

NOTE: Channel redundancy only applies to controllers that have more than one channel and that attach to an external disk enclosure.

Related Information:

Channel Redundancy on PERC 3/DCL, 3/DC, 3/QC, 4/DC, 4e/DC, 4/Di, and 4e/Di Controllers

The following considerations apply when creating a channel-redundant virtual disk on these controllers:

Creating a Channel-redundant Virtual Disk

The following instructions describe creating a virtual disk that uses channel redundancy.

NOTE: Channel redundancy only applies to controllers that have more than one channel and that attach to an external disk enclosure.
  1. Launch the Create Virtual Disk Advanced Wizard by doing the following:

    1. Locate the controller on which you are creating a channel-redundant virtual disk Expand the controller object until the Virtual Disks object is displayed.

    1. Select the Virtual Disks object and click Go To Create Virtual Disk Wizard.

    2. Click Virtual Disk Advanced Wizard.

  2. 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:

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. Refer to "Number of Physical Disks per Virtual Disk" for information on the number of physical disks that can be used for different RAID levels. Refer to "Controller-supported RAID Levels" for information on controller-specific implementations of the RAID levels.

Depending on the controller type, use one of the following procedures when completing "Create Virtual Disk Advanced Wizard (Step 2 of 4)":

Physical disk Selection for Channel-redundant Virtual Disks on PERC 3/DCL, 3/DC, 3/QC, 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 3/DCL, 3/DC, 3/QC, 4/DC, 4e/DC, 4/Di, or 4e/Di, controller.

RAID 10

    1. Select one physical disk on each of two channels. (In other words, each of the two channels will have a single disk selected.)

    1. Select an additional disk on each of the two channels. You have now selected the minimum number of disks for a RAID 10.

    2. Repeat step b until you have the desired number of disks.

    3. Click Continue.

RAID 50

    1. Select one physical disk on each of three channels. (In other words, each of the three channels will have a single disk selected.)

    1. Select an additional disk on each of the three channels. You have now selected the minimum number of disks for a RAID 50. Continue selecting a disk on each channel until you have selected the desired number of disks.

    2. Repeat step b until you have the desired number of disks.

    3. Click Continue.

Physical disk Selection for Channel-redundant Virtual Disks on a PERC 3/Di Controller:

The following section describes creating a channel-redundant virtual disk using RAID 10 or Concatenation of RAID 1 on a PERC 3/Di controller.

RAID 10 or Concatenation of RAID 1

    1. Select one physical disk on each of two channels. (In other words, each of the two channels will have a single disk selected.)

    1. Select an additional disk on each of the two channels. You have now selected the minimum number of disks for a RAID 10 or Concatenation of RAID 1.

    2. Repeat step b until you have selected the desired number of disks. You must select the same number of physical disks on each channel that you use.

    3. Click Continue.

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. 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 Alert Messages and Troubleshooting.

Severity

Component Status

Normal/OK. The component is working as expected.

Warning/Non-critical. A probe or other monitoring device has detected a reading for the component that is above or below the acceptable level. The component may still be functioning, but it could fail. The component may also be functioning in an impaired state. Data loss is possible.

Critical/Failure/Error. The component has either failed or failure is imminent. The component requires immediate attention and may need to be replaced. Data loss may have occurred.

Connector Information

For information on the connector, see the following topics:

Connector Components

For information on attached components, see the following topics:

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:

Property

Definition

These icons represent the severity or health of the storage component. See "Storage Component Severity" for more information. A Warning or Critical severity may indicate that the connector is unable to communicate with attached devices such as an enclosure. Check the status of attached devices. See "Cables Attached Correctly" and "Isolate Hardware Problems" for more information.

Name

This property displays the connector number.

State

This property displays the current status of the connector. Possible values are:

Ready — The connector is functioning normally.

Degraded — The connector has suffered a failure and is operating in a degraded state.

Failed — The connector has suffered a failure and is no longer functioning.

Connector Type

This property displays whether the connector is operating in RAID or SCSI mode. Depending on the controller type, the connector can be either a SCSI connector or a SAS port.

Termination

This property indicates the termination type of the connector.

Narrow — Indicates an 8 bit data bus.

Wide — Indicates a 16 bit data bus.

Unknown — Indicates that the termination type is unknown.

Not Terminated — On a SCSI controller, this property indicates that the data bus is not terminated. This property is also displayed when the termination type is unknown.

SCSI Rate

This property displays the SCSI speed for a SCSI device.

Connector Tasks: Rescan Connector

Does my controller support this feature? See "Appendix: 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 when you may want to do a rescan, see "Rescan to Update Storage Configuration Changes".

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).

Do the following to rescan a controller connector:

  1. Expand the Storage tree object to display the controller objects.

  2. Expand a controller object.

  3. Select a Connector object.

  4. Select the Information/Configuration subtab.

  5. Select Rescan from the Available Tasks drop-down menu.

  6. Click Execute.

Connector Components

For information on attached components, see the following topics:


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