Adding MDisks to an MDisk group

Use the Adding MDisk to an MDisk group panel in the SAN Volume Controller Console to add managed disks (MDisks) to an MDisk group.

Introduction

MDisks that belong to a group must be removed from their current group before you can assign them to a different group. In addition the warning threshold of the MDisk group is increased in proportion to the size of the MDisk that is added. The MDisks Candidates list contains all of the MDisks in the cluster that have a mode of unmanaged.
Note: The first time that you add a new solid-state drive (SSD) to an MDisk group, the SSD is automatically formatted and set to a block size of 512 bytes.

Attributes

The following attributes are displayed in the table:
Select
Allows you to select the MDisks to add to the MDisk group.
Note: Only one row can be selected at a time.
Name
Displays the name of the MDisk.
State
Displays the current state of the MDisk. The following values are possible:
Online
Indicates that the MDisk is online and available. All paths to the MDisk are available.
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 that 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 svctask includemdisk CLI command.
Offline
Indicates that the MDisk is offline and unavailable. All paths to this MDisk have been lost.
Capacity
Displays the capacity of the MDisk.

Actions

The following actions are available:

OK
Click this button to add MDisks to a group.
Cancel
Click this button to exit this panel without adding MDisks.
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