If you want to use specific device to hold your disk group configuration copy, you can change the attribute "keepmeta" value from "default"to "always". The benefit of this is if you have a new device that you initialized with bigger private region size, the number of VM objects that can be kept in the VM config database will also increase.

Below are the sample steps:

1.Initialize the new disk specifying the desired VM private region size.

vxdisksetup -if c1t13d0privlen=131072     <------ Initialized the device with private region size twice the default value (65536). The length depends on the sector count on the device via prtvtoc command

vxdisk list
DEVICE      TYPE            DISK        GROUP        STATUS
c0t0d0s2    auto            -            -            error
c1t2d0s2    auto:cdsdisk    workdg01     workdg      online
c1t8d0s2    auto:cdsdisk    testdg01     testdg      online
c1t9d0s2    auto:cdsdisk    testdg02     testdg      online
c1t12d0s2    auto:cdsdisk    testdg03    testdg      online
c1t13d0s2    auto:cdsdisk    -            -            online    <------Newly initialized device
c1t14d0s2    auto:cdsdisk    testdg05    testdg       online
 

 

vxdisklist c1t13d0  | egrep 'private | config'
flags:     onlineready private autoconfig autoimport
public:    slice=2offset=131328 len=17771616 disk_offset=0
private:   slice=2offset=256 len=131072 disk_offset=0    <------   Privateregion size
configs:   count=1 len=96528
logs:      count=1 len=14624
config   priv000048-000239[000192]: copy=01 offset=000000 disabled
config   priv000256-096591[096336]: copy=01 offset=000192 disabled



2.Currently, the disk group has only two configuration copies enabled

vxdg list testdg
Group:    testdg
dgid:      1199733338.25.kenkoy
import-id:1024.34
flags:     cds
version:   140
alignment: 8192(bytes)
local-activation:read-write
ssb:            on
detach-policy:global
dg-fail-policy: dgdisable
copies:    nconfig=2nlog=2
config:    seqno=0.1568 permlen=48144 free=48134 templen=6loglen=7296
config disk c1t8d0s2 copy 1 len=48144 disabled
config diskc1t9d0s2 copy 1 len=48144 state=clean online
config disk c1t12d0s2 copy 1len=48144 state=clean online
config disk c1t14d0s2 copy 1 len=48144disabled
log disk c1t8d0s2 copy 1 len=7296
log disk c1t9d0s2 copy 1len=7296 disabled
log disk c1t12d0s2 copy 1 len=7296
log disk c1t14d0s2copy 1 len=7296 disabled


3.  Add the disk to the disk group.

 

 

vxdisklist
DEVICE      TYPE            DISK        GROUP        STATUS
c0t0d0s2    auto            -            -            error
c1t2d0s2    auto:cdsdisk    workdg01     workdg      online
c1t8d0s2    auto:cdsdisk    testdg01     testdg      online
c1t9d0s2    auto:cdsdisk    testdg02     testdg      online
c1t12d0s2    auto:cdsdisk    testdg03    testdg      online
c1t13d0s2    auto:cdsdisk    testdg04    testdg       online   <------
c1t14d0s2    auto:cdsdisk    testdg05    testdg       online

vxdg listtestdg
Group:    testdg
dgid:      1199733338.25.kenkoy
import-id:1024.34
flags:     cds
version:   140
alignment: 8192(bytes)
local-activation:read-write
ssb:            on
detach-policy:global
dg-fail-policy: dgdisable
copies:    nconfig=2nlog=2
config:    seqno=0.1570 permlen=48144 free=48133 templen=6loglen=7296
config disk c1t8d0s2 copy 1 len=48144 disabled
config diskc1t9d0s2 copy 1 len=48144 state=clean online
config disk c1t12d0s2 copy 1len=48144 state=clean online
config disk c1t13d0s2 copy 1 len=96528disabled  <---- Notice that they are disabled.
config diskc1t14d0s2 copy 1 len=48144 disabled
log disk c1t8d0s2 copy 1 len=7296
logdisk c1t9d0s2 copy 1 len=7296 disabled
log disk c1t12d0s2 copy 1len=7296
log disk c1t13d0s2 copy 1 len=14624 disabled
log disk c1t14d0s2copy 1 len=7296 disabled


4.  We can set the device to have VM disk group configuration copy be enabled.
 
 vxdisk -g testdg settestdg04 keepmeta=always
     tander@kenkoy [/tander]vxdisklist
           DEVICE      TYPE            DISK        GROUP        STATUS
           c0t0d0s2    auto            -            -            error
           c1t2d0s2    auto:cdsdisk    workdg01     workdg      online
           c1t8d0s2    auto:cdsdisk    testdg01     testdg      online
           c1t9d0s2    auto:cdsdisk    testdg02     testdg      online
           c1t12d0s2    auto:cdsdisk    testdg03    testdg      online
           c1t13d0s2    auto:cdsdisk    testdg04    testdg       onlinekeepmeta
           c1t14d0s2    auto:cdsdisk    testdg05    testdg       online


5. Increase the numberof  VM configuration copy.

vxeditset nconfig=3 testdg

vxdg listtestdg
Group:    testdg
dgid:      1199733338.25.kenkoy
import-id:1024.34
flags:     cds
version:   140
alignment: 8192(bytes)
local-activation:read-write
ssb:            on
detach-policy:global
dg-fail-policy: dgdisable
copies:    nconfig=3nlog=2
config:    seqno=0.1572 permlen=48144 free=48133 templen=6loglen=7296
config disk c1t8d0s2 copy 1 len=48144 disabled
config diskc1t9d0s2 copy 1 len=48144 state=clean online
config disk c1t12d0s2 copy 1len=48144 state=clean online
config disk c1t13d0s2 copy 1 len=96528state=clean online
config disk c1t14d0s2 copy 1 len=48144disabled
log disk c1t8d0s2 copy 1 len=7296
log disk c1t9d0s2 copy 1len=7296 disabled
log disk c1t12d0s2 copy 1 len=7296
log disk c1t13d0s2copy 1 len=14624
log disk c1t14d0s2 copy 1 len=7296disabled
 

Note: You can change the number of configuration copy if desired.


 \\\ On the sample above it shows c1t14d0 as disabled... We will change the attribute (keepmeta) of this device to"always".

vxdisk -g testdg settestdg05 keepmeta=always

vxdisk list | grep keepmeta
 c1t13d0s2    auto:cdsdisk    testdg04    testdg       online keepmeta
 c1t14d0s2    auto:cdsdisk    testdg05    testdg       online keepmeta

  \\\ Setting back the diskgroup config copy to 2.

vxeditset nconfig=2 testdg

 

vxdg listtestdg
   Group:    testdg
   dgid:      1199733338.25.kenkoy
   import-id:1024.34
   flags:    cds
   version:   140
   alignment: 8192(bytes)
   local-activation:read-write
   ssb:            on
   detach-policy:global
   dg-fail-policy:dgdisable
   copies:    nconfig=2nlog=2
   config:    seqno=0.1578 permlen=48144free=48133 templen=6 loglen=7296
   config disk c1t8d0s2 copy 1len=48144 state=clean online
   config disk c1t9d0s2 copy 1len=48144 disabled
   config disk c1t12d0s2 copy 1 len=48144disabled
   config disk c1t13d0s2 copy 1 len=96528state=clean online <------ It holds now the VM disk group configuration copy.
   config disk c1t14d0s2 copy 1 len=48144state=clean online <------
   log disk c1t8d0s2 copy 1len=7296
   log disk c1t9d0s2 copy 1 len=7296disabled
   log disk c1t12d0s2 copy 1 len=7296disabled
   log disk c1t13d0s2 copy 1len=14624
   log disk c1t14d0s2 copy 1len=7296