Discovering managed disks

Use the Discovering Managed Disk panel in the SAN Volume Controller Console to rescan the fibre-channel network. The rescan discovers any new managed disks (MDisks) that might have been added to the cluster and rebalances MDisk access across the available controller device ports.

Introduction

In general, the cluster automatically detects MDisks that are added to the network. However, in some cases, the manufacturers of fibre-channel controllers do not send the required small computer system interface (SCSI) directives necessary to automatically discover the new MDisks.

Attributes

If new MDisks are discovered, the following attributes are displayed in the table:

Name
Displays the name of the MDisk.
State
Displays the state of the MDisk. The following values are possible:
Offline
Indicates the MDisk is offline and unavailable. All paths to this MDisk have been lost.
Degraded Paths
Indicates that the MDisk is not accessible to one or more nodes in the cluster. Degraded path state is most likely the result of incorrect configuration of either the disk controller or the fibre-channel fabric. However, hardware failures in the disk controller, fibre-channel fabric, or node could also be a contributing factor to this state. Complete the following actions to recover from this state:
  1. Verify that the fabric configuration rules for storage systems are correct.
  2. Ensure that you have configured the storage system properly.
  3. Correct any errors in the error log.
Degraded Ports
Indicates that one or more 1220 errors have been logged against the selected MDisk. The 1220 error indicates that the remote fibre-channel port has been excluded from the MDisk. This error may cause reduced performance on the storage controller and usually indicates a hardware problem with the storage controller. To fix this problem you must resolve any hardware problems on the storage controller and fix the 1220 errors in the error log. To resolve these errors in the log, select Service and Maintenance > Run Maintenance Procedures. On the Maintenance Procedures panel, select Start Analysis. This action displays a list of unfixed errors that are currently in the error log. For these unfixed errors, select the error name to begin a guided maintenance procedure to resolve these errors. Errors are listed in descending order with the highest priority error listed first. Highest priority errors should be resolved first.
Excluded
Indicates the MDisk has been excluded from use by the cluster after repeated access errors. Run the directed maintenance procedures to determine the problem. You can reset an MDisk and include it in the cluster by running the include task.
Online
Indicates the MDisk is online and available. All paths to the MDisk are available.
Capacity (MB)
Displays the capacity of the MDisk in megabytes.
Controller Name
Displays the name of the disk controller system that contains the MDisk.
Controller LUN Number
Displays the logical unit number for the MDisk on the disk controller system.

Actions

The following actions are available:

Close
Click this button to exit this panel.
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