Vxassist relayout does not use all specified disks when changing layout configuration
Article ID: 100044317
Updated On:
Cause
This is by design.
When converting a volume from one layout to another, the allocation engine may decide to use one of the original source disks and remaining target disks during the conversion process.
This is normally seen when performing a relayout from a concat to stripe volume.
In this instance, the concat volume spans multiple subdisks and the new stripe layout consists of multiple columns. The first column will normally remain using the source disk, where the alternate columns will use the specified target disks.
Example
A test volume is creating using 3 disks located on emc_clariion0_56, emc_clariion0_57 and emc_clariion0_58:
# vxassist -g testdg make vol01 28g
# vxprint -qhtg testdg
dg testdg default default 22000 1540305331.51.donald
dm emc_clariion0_56 emc_clariion0_56 auto 65536 20904976 -
dm emc_clariion0_57 emc_clariion0_57 auto 65536 20904976 -
dm emc_clariion0_58 emc_clariion0_58 auto 65536 20904976 -
dm emc_clariion0_59 emc_clariion0_59 auto 65536 20904976 -
dm emc_clariion0_60 emc_clariion0_60 auto 65536 20904976 -
dm emc_clariion0_61 emc_clariion0_61 auto 65536 20904976 -
v vol01 - ENABLED ACTIVE 58720256 SELECT - fsgen
pl vol01-01 vol01 ENABLED ACTIVE 58720256 CONCAT - RW
sd emc_clariion0_56-01 vol01-01 emc_clariion0_56 0 20904976 0 emc_clariion0_56 ENA
sd emc_clariion0_57-01 vol01-01 emc_clariion0_57 0 20904976 20904976 emc_clariion0_57 ENA
sd emc_clariion0_58-01 vol01-01 emc_clariion0_58 0 16910304 41809952 emc_clariion0_58 ENA
The relayout operation is selected to use target disks emc_clariion59, emc_clariion60 and emc_clariion61:
# vxassist -g testdg -o force relayout vol01 layout=stripe ncol=3 alloc=emc_clariion0_59,emc_clariion0_60,emc_clariion0_61 &
[1] 32751
# vxtask -l list
Task: 166 RUNNING
Type: RELAYOUT
Operation: RELAYOUT Vol vol01 Dg testdg
Started: Wed 24 Oct 2018 02:47:54 AM EDT
Throttle: 0
Throttle time: 0
Progress: 0.54%630784 of 117440512 Blocks
Work time: 3 second(s) (09:15 remaining)
# vxassist -g testdg -o force relayout vol01 layout=stripe ncol=3 alloc=emc_clariion0_59,emc_clariion0_60,emc_clariion0_61 &
[1] 32751
# vxtask -l list
Task: 166 RUNNING
Type: RELAYOUT
Operation: RELAYOUT Vol vol01 Dg testdg
Started: Wed 24 Oct 2018 02:47:54 AM EDT
Throttle: 0
Throttle time: 0
Progress: 0.54%630784 of 117440512 Blocks
Work time: 3 second(s) (09:15 remaining)
The vxrelayout progress can also be monitored by running:
# vxrelayout -g testdg status vol01
CONCAT --> STRIPED, columns=3, stwidth=128
Relayout running, 10.00% completed.
# vxrelayout -g testdg status vol01
CONCAT --> STRIPED, columns=3, stwidth=128
Relayout running, 30.00% completed.
CONCAT --> STRIPED, columns=3, stwidth=128
Relayout running, 10.00% completed.
# vxrelayout -g testdg status vol01
CONCAT --> STRIPED, columns=3, stwidth=128
Relayout running, 30.00% completed.
Once the relayout conversion is complete, only two of the specified target disks are used, emc_clariion0_59 and emc_clariion0_60:
# vxprint -qhtg testdg
dg testdg default default 22000 1540305331.51.donald
dm emc_clariion0_56 emc_clariion0_56 auto 65536 20904976 -
dm emc_clariion0_57 emc_clariion0_57 auto 65536 20904976 -
dm emc_clariion0_58 emc_clariion0_58 auto 65536 20904976 -
dm emc_clariion0_59 emc_clariion0_59 auto 65536 20904976 -
dm emc_clariion0_60 emc_clariion0_60 auto 65536 20904976 -
dm emc_clariion0_61 emc_clariion0_61 auto 65536 20904976 -
v vol01 - ENABLED ACTIVE 58720256 SELECT - fsgen
pl vol01-01 vol01 ENABLED ACTIVE 58720512 STRIPE 3/128 RW
sd emc_clariion0_56-03 vol01-01 emc_clariion0_56 0 19573504 0/0 emc_clariion0_56 ENA <<< still using one of the orig disks
sd emc_clariion0_59-03 vol01-01 emc_clariion0_59 0 19573504 1/0 emc_clariion0_59 ENA
sd emc_clariion0_60-03 vol01-01 emc_clariion0_60 0 19573504 2/0 emc_clariion0_60 ENA
NOTE: emc_clariion56 the original source disk is allocated to column 1 and emc_clariion0_61 is not used.
Only additional columns are allocated using the user specified target disks. The first column will always use the source disk allocated to the original source volume layout.
Resolution
Whilst this is not ideal in all cases, the vxassist mirroring function can be used to create a new plex with the new volume layout of your choice spanning the required disks to be used.
Example shown below:
The original test volume is deleted for testing purposes
# vxedit -g testdg -rf rm vol01
The volume is created again for the mirroring test
# vxassist -g testdg make vol01 28g
# vxprint -qhtg testdg
dg testdg default default 22000 1540305331.51.donald
dm emc_clariion0_56 emc_clariion0_56 auto 65536 20904976 -
dm emc_clariion0_57 emc_clariion0_57 auto 65536 20904976 -
dm emc_clariion0_58 emc_clariion0_58 auto 65536 20904976 -
dm emc_clariion0_59 emc_clariion0_59 auto 65536 20904976 -
dm emc_clariion0_60 emc_clariion0_60 auto 65536 20904976 -
dm emc_clariion0_61 emc_clariion0_61 auto 65536 20904976 -
v vol01 - ENABLED ACTIVE 58720256 SELECT - fsgen
pl vol01-01 vol01 ENABLED ACTIVE 58720256 CONCAT - RW
sd emc_clariion0_56-01 vol01-01 emc_clariion0_56 0 20904976 0 emc_clariion0_56 ENA
sd emc_clariion0_57-01 vol01-01 emc_clariion0_57 0 20904976 20904976 emc_clariion0_57 ENA
sd emc_clariion0_58-01 vol01-01 emc_clariion0_58 0 16910304 41809952 emc_clariion0_58 ENA
pl vol01-01 vol01 ENABLED ACTIVE 58720256 CONCAT - RW
sd emc_clariion0_56-01 vol01-01 emc_clariion0_56 0 20904976 0 emc_clariion0_56 ENA
sd emc_clariion0_57-01 vol01-01 emc_clariion0_57 0 20904976 20904976 emc_clariion0_57 ENA
sd emc_clariion0_58-01 vol01-01 emc_clariion0_58 0 16910304 41809952 emc_clariion0_58 ENA
# vxassist -g testdg -o force mirror vol01 layout=stripe ncol=3 alloc=emc_clariion0_59,emc_clariion0_60,emc_clariion0_61 &
[1] 156565
# vxprint -qhtg testdg
dg testdg default default 22000 1540305331.51.donald
dg testdg default default 22000 1540305331.51.donald
dm emc_clariion0_56 emc_clariion0_56 auto 65536 20904976 -
dm emc_clariion0_57 emc_clariion0_57 auto 65536 20904976 -
dm emc_clariion0_58 emc_clariion0_58 auto 65536 20904976 -
dm emc_clariion0_59 emc_clariion0_59 auto 65536 20904976 -
dm emc_clariion0_60 emc_clariion0_60 auto 65536 20904976 -
dm emc_clariion0_61 emc_clariion0_61 auto 65536 20904976 -
v vol01 - ENABLED ACTIVE 58720256 SELECT - fsgen
pl vol01-01 vol01 ENABLED ACTIVE 58720256 CONCAT - RW
sd emc_clariion0_56-01 vol01-01 emc_clariion0_56 0 20904976 0 emc_clariion0_56 ENA
sd emc_clariion0_57-01 vol01-01 emc_clariion0_57 0 20904976 20904976 emc_clariion0_57 ENA
sd emc_clariion0_58-01 vol01-01 emc_clariion0_58 0 16910304 41809952 emc_clariion0_58 ENA
pl vol01-02 vol01 ENABLED TEMPRMSD 58720512 STRIPE 3/128 WO
sd emc_clariion0_59-01 vol01-02 emc_clariion0_59 0 19573504 0/0 emc_clariion0_59 ENA
sd emc_clariion0_60-01 vol01-02 emc_clariion0_60 0 19573504 1/0 emc_clariion0_60 ENA
sd emc_clariion0_61-01 vol01-02 emc_clariion0_61 0 19573504 2/0 emc_clariion0_61 ENA
The mirroring time can be reviewed using the below command:
pl vol01-01 vol01 ENABLED ACTIVE 58720256 CONCAT - RW
sd emc_clariion0_56-01 vol01-01 emc_clariion0_56 0 20904976 0 emc_clariion0_56 ENA
sd emc_clariion0_57-01 vol01-01 emc_clariion0_57 0 20904976 20904976 emc_clariion0_57 ENA
sd emc_clariion0_58-01 vol01-01 emc_clariion0_58 0 16910304 41809952 emc_clariion0_58 ENA
pl vol01-02 vol01 ENABLED TEMPRMSD 58720512 STRIPE 3/128 WO
sd emc_clariion0_59-01 vol01-02 emc_clariion0_59 0 19573504 0/0 emc_clariion0_59 ENA
sd emc_clariion0_60-01 vol01-02 emc_clariion0_60 0 19573504 1/0 emc_clariion0_60 ENA
sd emc_clariion0_61-01 vol01-02 emc_clariion0_61 0 19573504 2/0 emc_clariion0_61 ENA
The mirroring time can be reviewed using the below command:
# vxtask -l list
Task: 183 RUNNING
Type: ATCOPY
Operation: PLXATT Vol vol01 Plex vol01-02 Dg testdg
Started: Mon 29 Oct 2018 05:26:51 AM EDT
Throttle: auto-throttled
Throttle time: 0 seconds
Progress: 76.41%44869632 of 58720256 Blocks
Work time: 2 minute(s) 8 second(s) (0:39 remaining)
Task: 183 RUNNING
Type: ATCOPY
Operation: PLXATT Vol vol01 Plex vol01-02 Dg testdg
Started: Mon 29 Oct 2018 05:26:51 AM EDT
Throttle: auto-throttled
Throttle time: 0 seconds
Progress: 76.41%44869632 of 58720256 Blocks
Work time: 2 minute(s) 8 second(s) (0:39 remaining)
The new mirror is using the specified target disks:
# vxprint -qhtg testdg
dg testdg default default 22000 1540305331.51.donald
# vxprint -qhtg testdg
dg testdg default default 22000 1540305331.51.donald
dm emc_clariion0_56 emc_clariion0_56 auto 65536 20904976 -
dm emc_clariion0_57 emc_clariion0_57 auto 65536 20904976 -
dm emc_clariion0_58 emc_clariion0_58 auto 65536 20904976 -
dm emc_clariion0_59 emc_clariion0_59 auto 65536 20904976 -
dm emc_clariion0_60 emc_clariion0_60 auto 65536 20904976 -
dm emc_clariion0_61 emc_clariion0_61 auto 65536 20904976 -
v vol01 - ENABLED ACTIVE 58720256 SELECT - fsgen
pl vol01-01 vol01 ENABLED ACTIVE 58720256 CONCAT - RW
sd emc_clariion0_56-01 vol01-01 emc_clariion0_56 0 20904976 0 emc_clariion0_56 ENA
sd emc_clariion0_57-01 vol01-01 emc_clariion0_57 0 20904976 20904976 emc_clariion0_57 ENA
sd emc_clariion0_58-01 vol01-01 emc_clariion0_58 0 16910304 41809952 emc_clariion0_58 ENA
pl vol01-02 vol01 ENABLED ACTIVE 58720512 STRIPE 3/128 RW
sd emc_clariion0_59-01 vol01-02 emc_clariion0_59 0 19573504 0/0 emc_clariion0_59 ENA
sd emc_clariion0_60-01 vol01-02 emc_clariion0_60 0 19573504 1/0 emc_clariion0_60 ENA
sd emc_clariion0_61-01 vol01-02 emc_clariion0_61 0 19573504 2/0 emc_clariion0_61 ENA
[1]+ Done vxassist -g testdg -o force mirror vol01 layout=stripe ncol=3 alloc=emc_clariion0_59,emc_clariion0_60,emc_clariion0_61
pl vol01-01 vol01 ENABLED ACTIVE 58720256 CONCAT - RW
sd emc_clariion0_56-01 vol01-01 emc_clariion0_56 0 20904976 0 emc_clariion0_56 ENA
sd emc_clariion0_57-01 vol01-01 emc_clariion0_57 0 20904976 20904976 emc_clariion0_57 ENA
sd emc_clariion0_58-01 vol01-01 emc_clariion0_58 0 16910304 41809952 emc_clariion0_58 ENA
pl vol01-02 vol01 ENABLED ACTIVE 58720512 STRIPE 3/128 RW
sd emc_clariion0_59-01 vol01-02 emc_clariion0_59 0 19573504 0/0 emc_clariion0_59 ENA
sd emc_clariion0_60-01 vol01-02 emc_clariion0_60 0 19573504 1/0 emc_clariion0_60 ENA
sd emc_clariion0_61-01 vol01-02 emc_clariion0_61 0 19573504 2/0 emc_clariion0_61 ENA
[1]+ Done vxassist -g testdg -o force mirror vol01 layout=stripe ncol=3 alloc=emc_clariion0_59,emc_clariion0_60,emc_clariion0_61
Issue/Introduction
When changing the volume layout configuration using the relayout feature, the operation may not use all the specfiied disk names. As a result, it may be required to manually migrate the contents of a subdisk(s) to the desired target disk manually using commands such as vxassist move.
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