How to perform Backup and Restore of ASM Metadata

[grid@erpdcdb01 ~]$ asmcmd
ASMCMD> md_backup /u01/Stage/asmbackup/asmmetadata.backup -G RMAN_BKP
Disk group metadata to be backed up: RMAN_BKP
Current alias directory path: ASM
Current alias directory path: SBLCBS/BACKUPSET
Current alias directory path: SBLCBS/BACKUPSET/2016_11_29
Current alias directory path: SBLCBS/BACKUPSET/2016_12_06
Current alias directory path: SBLCBS
Current alias directory path: ASM/DUMPSET
ASMCMD> exit
[grid@erpdcdb01 ~]$
[grid@erpdcdb01 ~]$ srvctl status diskgroup -g RMAN_BKP
Disk Group RMAN_BKP is running on erpdcdb01,erpdcdb02
[grid@erpdcdb01 ~]$ srvctl stop diskgroup -g RMAN_BKP -f
[grid@erpdcdb01 ~]$ srvctl status diskgroup -g RMAN_BKP
Disk Group RMAN_BKP is not running
[grid@erpdcdb01 ~]$ srvctl remove  diskgroup -g RMAN_BKP -f
[grid@erpdcdb01 ~]$ srvctl status diskgroup -g RMAN_BKP
PRCA-1000 : ASM Disk Group RMAN_BKP does not exist
PRCR-1001 : Resource ora.RMAN_BKP.dg does not exist
[grid@erpdcdb01 ~]$ asmcmd lsdg -g
Inst_ID  State    Type    Rebal  Sector  Block       AU  Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  Name
      2  MOUNTED  EXTERN  N         512   4096  1048576    322553   288859                0          288859              0             N  DATA/
      1  MOUNTED  EXTERN  N         512   4096  1048576    322553   288859                0          288859              0             N  DATA/
      2  MOUNTED  EXTERN  N         512   4096  1048576     92158    61454                0           61454              0             N  FRA/
      1  MOUNTED  EXTERN  N         512   4096  1048576     92158    61454                0           61454              0             N  FRA/
      2  MOUNTED  NORMAL  N         512   4096  1048576     12285    11359             4095            3632              0             Y  OCR/
      1  MOUNTED  NORMAL  N         512   4096  1048576     12285    11359             4095            3632              0             Y  OCR/
[grid@erpdcdb01 ~]$
[grid@erpdcdb01 ~]$ sqlplus "/as sysasm"

SQL*Plus: Release 11.2.0.4.0 Production on Tue Dec 6 07:57:24 2016

Copyright (c) 1982, 2013, Oracle.  All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Real Application Clusters and Automatic Storage Management options

SQL> # drop diskgroup RMAN_BKP FORCE INCLUDING CONTENTS;
Don't perform this in production. It will drop data from your diskgroup.

Diskgroup dropped.

SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Real Application Clusters and Automatic Storage Management options
[grid@erpdcdb01 ~]$
[grid@erpdcdb01 ~]$ asmcmd
ASMCMD> md_restore /u01/Stage/asmbackup/asmmetadata.backup  --full
Current Diskgroup metadata being restored: RMAN_BKP
Diskgroup RMAN_BKP created!
System template AUTOBACKUP modified!
System template DATAFILE modified!
System template DUMPSET modified!
System template OCRFILE modified!
System template PARAMETERFILE modified!
System template ASMPARAMETERFILE modified!
System template CHANGETRACKING modified!
System template ONLINELOG modified!
System template CONTROLFILE modified!
System template BACKUPSET modified!
System template XTRANSPORT modified!
System template FLASHBACK modified!
System template DATAGUARDCONFIG modified!
System template TEMPFILE modified!
System template FLASHFILE modified!
System template XTRANSPORT BACKUPSET modified!
System template ARCHIVELOG modified!
Directory +RMAN_BKP/SBLCBS re-created!
Directory +RMAN_BKP/ASM re-created!
Directory +RMAN_BKP/SBLCBS/BACKUPSET re-created!
Directory +RMAN_BKP/ASM/DUMPSET re-created!
Directory +RMAN_BKP/SBLCBS/BACKUPSET/2016_12_06 re-created!
Directory +RMAN_BKP/SBLCBS/BACKUPSET/2016_11_29 re-created!
ASMCMD> exit
[grid@erpdcdb01 ~]$
[grid@erpdcdb01 ~]$ asmcmd
ASMCMD> lsdg
State    Type    Rebal  Sector  Block       AU  Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  Name
MOUNTED  EXTERN  N         512   4096  1048576    322553   288859                0          288859              0             N  DATA/
MOUNTED  EXTERN  N         512   4096  1048576     92158    61454                0           61454              0             N  FRA/
MOUNTED  NORMAL  N         512   4096  1048576     12285    11359             4095            3632              0             Y  OCR/
MOUNTED  EXTERN  N         512   4096  1048576     92158    92104                0           92104              0             N  RMAN_BKP/
ASMCMD> exit
[grid@erpdcdb01 ~]$
[grid@erpdcdb01 ~]$ srvctl status diskgroup -g RMAN_BKP
Disk Group RMAN_BKP is running on sbldcdb01
[grid@erpdcdb01 ~]$ srvctl stop diskgroup -g RMAN_BKP
[grid@erpdcdb01 ~]$ srvctl start diskgroup -g RMAN_BKP