RAID 5 Volumes (Tasks)

This chapter provides information about performing Solaris Volume Manager tasks that are associated with RAID 5 volumes. For information about the concepts involved in these tasks, see Chapter 13, RAID 5 Volumes (Overview).

RAID 5 Volumes (Task Map)

The following task map identifies the procedures needed to manage Solaris Volume Manager RAID 5 volumes.

Creating RAID 5 Volumes

How to Create a RAID 5 Volume

1. Check "Prerequisites for Creating Solaris Volume Manager Elements" and "Background Information for Creating RAID 5 Volumes".

2. To create the RAID 5 volume, use one of the following methods:

   • From the Enhanced Storage tool within the Solaris Management Console, open the Volumes node, then choose Action->Create Volume and follow the steps in the wizard. For more information, see the online help.

   • Use the following form of the metainit command:

     metainit name -r component component component

     • name is the name for the volume to create.

     • r specifies to create a RAID 5 volume.

     • component specifies a slice or soft partition to include in the RAID 5 volume.

     To specify an interlace value, add the -i interlace-value option. For more information, see the metainit(1M) man page.

Example--Creating a RAID 5 Volume of Three Slices

# metainit d45 -r c2t3d0s2 c3t0d0s2 c4t0d0s2
d45: RAID is setup

In this example, the RAID 5 volume d45 is created with the -r option from three slices. Because no interlace value is specified, d45 uses the default of 16 Kbytes. The system verifies that the RAID 5 volume has been set up, and begins initializing the volume.

Note - You must wait for the initialization to finish before you can use the RAID 5 volume.

Where to Go From Here

To prepare the newly created RAID 5 volume for a file system, see "Creating File Systems (Tasks)" in System Administration Guide: Basic Administration. An application, such as a database, that uses the raw volume must have its own way of recognizing the volume.

To associate a hot spare pool with a RAID 5 volume, see "How to Associate a Hot Spare Pool With a Volume".

Maintaining RAID 5 Volumes

How to Check the Status of RAID 5 Volumes

• To check status on a RAID 5 volume, use one of the following methods:

  • From the Enhanced Storage tool within the Solaris Management Console, open the Volumes node and view the status of the volumes. Choose a volume, then choose Action->Properties to see more detailed information. For more information, see the online help.

  • Use the metastat command.

    For each slice in the RAID 5 volume, the metastat command shows the following:

    • "Device" (device name of the slice in the stripe)

    • "Start Block" on which the slice begins

    • "Dbase" to show if the slice contains a state database replica

    • "State" of the slice

    • "Hot Spare" to show the slice being used to hot spare a failed slice

Example--Viewing RAID 5 Volume Status

Here is sample RAID 5 volume output from the metastat command.

# metastat
d10: RAID
    State: Okay        
    Interlace: 32 blocks
    Size: 10080 blocks
Original device:
    Size: 10496 blocks
        Device              Start Block  Dbase State        Hot Spare
        c0t0d0s1                 330     No    Okay        
        c1t2d0s1                 330     No    Okay        
        c2t3d0s1                 330     No    Okay 

The metastat command output identifies the volume as a RAID 5 volume. For each slice in the RAID 5 volume, it shows the name of the slice in the stripe, the block on which the slice begins, an indicator that none of these slices contain a state database replica, that all the slices are okay, and that none of the slices are hot spare replacements for a failed slice.

RAID 5 Volume Status Information

The following table explains RAID 5 volume states.

Table 14-1 RAID 5 States

The slice state is perhaps the most important information when you are troubleshooting RAID 5 volume errors. The RAID 5 state only provides general status information, such as "Okay" or "Needs Maintenance." If the RAID 5 reports a "Needs Maintenance" state, refer to the slice state. You take a different recovery action if the slice is in the "Maintenance" or "Last Erred" state. If you only have a slice in the "Maintenance" state, it can be repaired without loss of data. If you have a slice in the "Maintenance" state and a slice in the "Last Erred" state, data has probably been corrupted. You must fix the slice in the "Maintenance" state first then the "Last Erred" slice. See "Overview of Replacing and Enabling Components in RAID 1 and RAID 5 Volumes".

The following table explains the slice states for a RAID 5 volume and possible actions to take.

Table 14-2 RAID 5 Slice States

Note - RAID 5 volume initialization or resynchronization cannot be interrupted.