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Product: Volume Manager Guides   
Manual: Volume Manager 4.1 Administrator's Guide   

Displaying Volume Information

You can use the vxprint command to display information about how a volume is configured.

To display the volume, plex, and subdisk record information for all volumes in the system, use the following command:


vxprint -hvt 

The vxprint command can also be applied to a single disk group:


vxprint -g mydg -hvt

This is example output from this command:


V  NAME     RVG/VSET/CO      KSTATE     STATE     LENGTH     READPOL      PREFPLEX      UTYPE
PL  NAME     VOLUME      KSTATE     STATE     LENGTH     LAYOUT      NCOL/WID      MODE
SD  NAME     PLEX      DISK     DISKOFFS     LENGTH     [COL/]OFF      DEVICE      MODE
SV  NAME     PLEX      VOLNAME     NVOLLAYR     LENGTH     [COL/]OFF      AM/NM      MODE
SC  NAME     PLEX      CACHE     DISKOFFS     LENGTH     [COL/]OFF      DEVICE      MODE
DC  NAME     PARENTVOL      LOGVOL
SP  NAME     SNAPVOL      DCO

v  pubs     -      ENABLED     ACTIVE     22880     SELECT      -      fsgen
pl  pubs-01      pubs      ENABLED     ACTIVE     22880     CONCAT      -      RW
sd  mydg11-01     pubs-01      mydg11     0     22880     0      c1t0d0      ENA

v  voldef     -      ENABLED     ACTIVE     20480     SELECT      -       fsgen
pl  voldef-01     voldef      ENABLED     ACTIVE     20480     CONCAT      -      RW
sd  mydg12-02     voldef-0      mydg12     0     20480     0      c1t1d0      ENA

Here v is a volume, pl is a plex, and sd is a subdisk. The top few lines indicate the headers that match each type of output line that follows. Each volume is listed along with its associated plexes and subdisks.


Note   Note    The headings for sub-volumes (SV), storage caches (SC), data change objects (DCO) and snappoints (SP) can be ignored here. No such objects are associated with these volumes.

To display volume-related information for a specific volume, use the following command:


vxprint [-g diskgroup] -t volume 

For example, to display information about the volume, voldef, in the disk group, mydg, use the following command:


vxprint -g mydg -t voldef

This is example output from this command:


V  NAME     RVG/VSET/CO      KSTATE     STATE     LENGTH     READPOL      PREFPLEX      UTYPE

v  voldef     -      ENABLED     ACTIVE     20480     SELECT      -      fsgen
Note   Note    If you enable enclosure-based naming, and use the vxprint command to display the structure of a volume, it shows enclosure-based disk device names (disk access names) rather than c#t#d# names. See Discovering the Association between Enclosure-Based Disk Names and OS-Based Disk Names for information on how to obtain the true device names.

The following section describes the meaning of the various volume states that may be displayed.

Volume States

The following volume states may be displayed by VxVM commands such as vxprint:

ACTIVE Volume State

The volume has been started (kernel state is currently ENABLED) or was in use (kernel state was ENABLED) when the machine was rebooted. If the volume is currently ENABLED, the state of its plexes at any moment is not certain (since the volume is in use).

If the volume is currently DISABLED, this means that the plexes cannot be guaranteed to be consistent, but are made consistent when the volume is started.

For a RAID-5 volume, if the volume is currently DISABLED, parity cannot be guaranteed to be synchronized.

CLEAN Volume State

The volume is not started (kernel state is DISABLED) and its plexes are synchronized. For a RAID-5 volume, its plex stripes are consistent and its parity is good.

EMPTY Volume State

The volume contents are not initialized. The kernel state is always DISABLED when the volume is EMPTY.

INVALID Volume State

The contents of an instant snapshot volume no longer represent a true point-in-time image of the original volume.

NEEDSYNC Volume State

The volume requires a resynchronization operation the next time it is started. For a RAID-5 volume, a parity resynchronization operation is required.

REPLAY Volume State

The volume is in a transient state as part of a log replay. A log replay occurs when it becomes necessary to use logged parity and data. This state is only applied to RAID-5 volumes.

SYNC Volume State

The volume is either in read-writeback recovery mode (kernel state is currently ENABLED) or was in read-writeback mode when the machine was rebooted (kernel state is DISABLED). With read-writeback recovery, plex consistency is recovered by reading data from blocks of one plex and writing the data to all other writable plexes. If the volume is ENABLED, this means that the plexes are being resynchronized through the read-writeback recovery. If the volume is DISABLED, it means that the plexes were being resynchronized through read-writeback when the machine rebooted and therefore still need to be synchronized.

For a RAID-5 volume, the volume is either undergoing a parity resynchronization (kernel state is currently ENABLED) or was having its parity resynchronized when the machine was rebooted (kernel state is DISABLED).


Note   Note    The interpretation of these flags during volume startup is modified by the persistent state log for the volume (for example, the DIRTY/CLEAN flag). If the clean flag is set, an ACTIVE volume was not written to by any processes or was not even open at the time of the reboot; therefore, it can be considered CLEAN. The clean flag is always set in any case where the volume is marked CLEAN.

Volume Kernel States

The volume kernel state indicates the accessibility of the volume. The volume kernel state allows a volume to have an offline (DISABLED), maintenance (DETACHED), or online (ENABLED) mode of operation.


Note   Note    No user intervention is required to set these states; they are maintained internally. On a system that is operating properly, all volumes are ENABLED.

The following volume kernel states are defined:

DETACHED Volume Kernel State

Maintenance is being performed on the volume. The volume cannot be read from or written to, but certain plex operations and ioctl function calls are accepted.

DISABLED Volume Kernel State

The volume is offline and cannot be accessed.

ENABLED Volume Kernel State

The volume is online and can be read from or written to.

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Product: Volume Manager Guides  
Manual: Volume Manager 4.1 Administrator's Guide  
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