By default, disks on which the udid_mismatch
flag or the clone_disk
flag has been set are not imported by the vxdg
import
command unless all disks in the disk group have at least one of these flags set, and no two of the disks have the same UDID. You can then import the cloned disks by specifying the-o
useclonedev=on
option to the vxdg
import
command, as shown in this example:
# vxdg -o useclonedev=on
[
-o updateid
]
import mydg
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 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 sdg sdh
Alternatively, you can update the UDIDs of the cloned disks.
See "Writing a new UDID to a disk" on page 186.
To check which disks are tagged, use the vxdisk
listtag
command:
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
\
To check which disks in a disk group contain copies of this configuration information, use the vxdg
listmeta
command:
# vxdg [-q] listmeta
diskgroup
The -q
option can be specified to suppress detailed configuration information from being displayed.
The tagged disks in the disk group may be imported by specifying the tag to the vxdg
import
command in addition to the -o
useclonedev=on
option:
# vxdg -o useclonedev=on -o tag=my_tagged_disks import mydg
If you have already imported the non-cloned disks in a disk group, you can use the -n
and -t
option to specify a temporary name for the disk group containing the cloned disks:
# vxdg -t -n clonedg -o useclonedev=on -o tag=my_tagged_disks \ import mydg
See "Renaming a disk group" on page 192.
To remove a tag from a disk, use the vxdisk
rmtag
command, as shown in the following example:
# vxdisk rmtag tag=my_tagged_disks sdh
See the vxdisk
(1M) and vxdg
(1M) manual pages.