Plex size and volume size is different

[agarwalamit1]

Hi,

Facing a problem where plex and volume size is different, i need to mirror the volume but while mirror it gives error. first we need to correct this unexpected behaviour of volume.

Volume is concat and i need to mirror it.

root:test1:/root # vxprint -htg asmm7 -htv volume

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 volume - ENABLED ACTIVE 419430400 SELECT - fsgen

pl volume-01 volume ENABLED ACTIVE 418426880 CONCAT - RW

sd asmm7_8-01 volume-01 asmm7_8 0 167270400 0 usp006_21 ENA

sd asmm7_9-01 volume-01 asmm7_9 0 167270400 167270400 usp006_19 ENA

sd asmm7_10-01 volume-01 asmm7_20 0 83886080 334540800 usp006_9 ENA

1) I created another plex of same size and tried to attach but get below message.

root:test1:/root # vxplex -g asmm7 att volume volume-02
VxVM vxplex ERROR V-5-1-4035 Plex volume-02 would be a sparse plex of Volume volume
　　　　　　　　use -o force to force the operation

root:test1:/root # vxplex -g asmm7 -o force att volume volume-02
VxVM vxplex ERROR V-5-1-1204 Volume volume has no complete plexes, cannot attach

2) Tried to mirror with vxassist command but no success.

vxassist -v -b -g asmm7 mirror　volume　layout=mirror-concat alloc="asmm7_21m asmm7_22m asmm7_23m"

root:test1:/root # VxVM vxplex ERROR V-5-1-1204 Volume volume has no complete plexes, cannot attach
VxVM vxassist ERROR V-5-1-502 Could not attach new mirror(s)　to volume volume

can someone help on it?

[Marianne]

Is this volume currently mounted and 'alive and well'?

If so, backup the filesystem, unmount the volume and recreate the volume as per TN http://www.symantec.com/docs/TECH67644

[mikebounds]

If you use the high level command "vxassist" then you won't have problems where the volume is a different size to plex, so I would not use the lower level commands (like vxplex and vxmake) to create your volumes, just use the single vxassist command which create subdisks, plexes and volumes and associates and starts them all for you.

Mike

[TonyGriffiths]

Hi,

The mirror attach operations are failing due to the addressable size of storage in the volume being larger than that of the plex assigned to it. i.e the volume has no complete plex that will store the entire volume data.

Volume length: 419430400
Plex length:   418426880

Do you know the history of the volume ? recently created ? if so by what method ? Any volume changes resizes etc ?

cheers

tony

[Nilesh_Joshi]

Issue resolved Amit.

Well, I got the link where it says -

http://www.symantec.com/business/support/index?page=content&id=TECH67644

- Remove the volume
- Then attached the plex to the volume.

Well, unfortunately this solution was not for me! So, I figured out another way -

So, there is 1003520 sector diffrence between Volume length and Plex length. So how about associating subdisk of size 1003520 sectors.... just wild idea - let's see how it goes...

root:XXXXXX:/root # vxmake -g asmm7 sd asmm7_10-04 asmm7_10,0,1003520
root:XXXXXX:/root # vxsd -g asmm7 assoc DXarchive90d-01 asmm7_10-04

BEFORE:

v  DXarchive90d -            ENABLED  ACTIVE   419430400 SELECT   -        fsgen
pl DXarchive90d-01 DXarchive90d ENABLED ACTIVE 418426880 CONCAT   -        RW
sd asmm7_8-01   DXarchive90d-01 asmm7_8 0      167270400 0        usp006_21 ENA
sd asmm7_9-01   DXarchive90d-01 asmm7_9 0      167270400 167270400 usp006_19 ENA
sd asmm7_10-01  DXarchive90d-01 asmm7_20 0     83886080 334540800 usp006_9 ENA

AFTER:

v  DXarchive90d -            ENABLED  ACTIVE   419430400 SELECT   -        fsgen
pl DXarchive90d-01 DXarchive90d ENABLED ACTIVE 419430400 CONCAT   -        RW
sd asmm7_8-01   DXarchive90d-01 asmm7_8 0      167270400 0        usp006_21 ENA
sd asmm7_9-01   DXarchive90d-01 asmm7_9 0      167270400 167270400 usp006_19 ENA
sd asmm7_10-01  DXarchive90d-01 asmm7_20 0     83886080 334540800 usp006_9 ENA
sd asmm7_10-04  DXarchive90d-01 asmm7_10 0     1003520  418426880 usp006_16 ENA

Good enough - the root cause of volume mirror not happening was mismatch between volume lenth and plex lenth so all what I did is matched those sizes by associating subdisk of the size of diffrence to existing plex. 

Execute -

root:XXXXXX:/root # vxassist -v -b -g asmm7 mirror DXarchive90d layout=mirror-concat alloc="asmm7_21m asmm7_22m asmm7_23m"

SUCCESS!!!! Mirroring done OK.

root:XXXXXX:/root #  vxtask -l list
Task:      559 RUNNING
Type:      ATCOPY
Operation: PLXATT Vol DXarchive90d Plex DXarchive90d-02 Dg asmm7
Started:   Thu Dec 06 12:07:12 2012
Throttle:  0
Progress:  46.95% 196917248 of 419430400 Blocks
Work time: 29 minutes, 12 seconds (32:59 remaining)

v  DXarchive90d -            ENABLED  ACTIVE   419430400 SELECT   -        fsgen
pl DXarchive90d-01 DXarchive90d ENABLED ACTIVE 419430400 CONCAT   -        RW
sd asmm7_8-01   DXarchive90d-01 asmm7_8 0      167270400 0        usp006_21 ENA
sd asmm7_9-01   DXarchive90d-01 asmm7_9 0      167270400 167270400 usp006_19 ENA
sd asmm7_10-01  DXarchive90d-01 asmm7_20 0     83886080 334540800 usp006_9 ENA
sd asmm7_10-04  DXarchive90d-01 asmm7_10 0     1003520  418426880 usp006_16 ENA
pl DXarchive90d-02 DXarchive90d ENABLED TEMPRMSD 419430400 CONCAT -        WO
sd asmm7_21m-01 DXarchive90d-02 asmm7_21m 0    167270400 0        usp009_20 ENA
sd asmm7_22m-01 DXarchive90d-02 asmm7_22m 0    167270400 167270400 usp009_21 ENA
sd asmm7_23m-01 DXarchive90d-02 asmm7_23m 0    84889600 334540800 usp009_22 ENA

Hope this helps!

-Nilesh Joshi