Creating and administering disk groups 177

Handling disks with duplicated identifiers

#vxdg -o useclonedev=on [-o updateid] import mydg

Note: This form of the command allows only cloned disks to be imported. All non-cloned disks remain unimported.

If the clone_disk flag is set on a disk, this indicates the disk was previously imported into a disk group with the udid_mismatch flag set.

The -o updateid option can be specified to write new identification attributes to the disks, and to set the clone_disk flag on the disks. (The vxdisk set clone=on command can also be used to set the flag.) However, the import fails if multiple copies of one or more cloned disks exist. In this case, you can either update the UDIDs of the cloned disks as described in “Writing a new UDID to a disk” on page 176, or you can use the following command to tag all the disks in the disk group that are to be imported:

#vxdisk [-g diskgroup] settag tagname disk ...

where tagname is a string of up to 128 characters, not including spaces or tabs. For example, the following command sets the tag, my_tagged_disks, on several disks that are to be imported together:

#vxdisk settag my_tagged_disks c2t66d0 c2t67d0

To check which disks are tagged, use the vxdisk listtag command:

#vxdisk listtag

DANAME

DMNAME

NAME

VALUE

c0t06d0

mydg01

-

-

c0t16d0

mydg02

-

-

...

 

 

 

c2t64d0

mydg05

my_tagged_disks

-

c2t65d0

mydg06

my_tagged_disks

-

c2t66d0

mydg07

my_tagged_disks

-

c2t67d0

mydg08

my_tagged_disks

-

c2t68d0

mydg09

-

-

The configuration database in a VM disk’s private region contains persistent configuration data (or metadata) about the objects in a disk group. This database is consulted by VxVM when the disk group is imported. At least one of the cloned disks that are being imported must contain a copy of the current configuration database in its private region.

You can use the following command to ensure that a copy of the metadata is placed on a disk, regardless of the placement policy for the disk group:

#vxdisk [-g diskgroup] set disk keepmeta=always

Alternatively, use the following command to place a copy of the configuration database and kernel log on all disks in a disk group that share a given tag:

#vxdg [-g diskgroup] set tagmeta=on tag=tagname nconfig=all \ nlog=all