3. Verify that volumes are visible on the database host(s)

The DR volumes should also be configured identically to the PROD volumes in the DR host OS. For instance, if using multipath I/O, the device mapper names and aliases should be the same.

3a. Rescan scsi bus

# rescan-scsi-bus.sh

3b. Add multipath aliases in /etc/multipath.conf

If there are a large number of volumes, it's easier to copy the multipath aliases from the PROD host and update the wwids.

3c. Restart the multipath service

# service multipathd restart

3d. Check device ownership

Make sure all dm- devices corresponding to the volume multipaths are owned by grid:asmadmin. Setup the required udev rules to set the device ownership if not done so already.

The devices should be visible as asm disks since they are already labeled as ASM disks.

3e. Mount disks

Scan the disks to make sure the latest state of the headers are read. In our case, we are using the ASM Filter Driver (AFD), therefore we use the afd_scan command in asmcmd. If you are using ASMLib for device persistance, use the oracleasm scandisks command.

[grid@sn1-r720-e03-05 ~]$ asmcmd 

ASMCMD> afd_scan

Login to asmcmd and run "lsdsk --discovery". It should be able to find the newly added disks.

ASMCMD>  lsdg --discovery
State       Type    Rebal  Sector  Logical_Sector  Block       AU  Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  Name
DISMOUNTED          N           0               0      0        0         0        0                0               0              0             N  ORAPRD12_DATA/
DISMOUNTED          N           0               0      0        0         0        0                0               0              0             N  ORAPRD12_FRA/
DISMOUNTED          N           0               0      0        0         0        0                0               0              0             N  ORAPRD12_REDO/

If the State is DISMOUNTED, mount the disk groups.

ASMCMD> mount ORAPRD12_DATA
ASMCMD> mount ORAPRD12_FRA
ASMCMD> mount ORAPRD12_REDO

Make sure that the State is MOUNTED before proceeding to the next step.

ASMCMD> lsdg
State    Type    Rebal  Sector  Logical_Sector  Block       AU  Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  Name
MOUNTED  EXTERN  N         512             512   4096  1048576   8388608  5407628                0         5407628              0             N  ORAPRD12_DATA/
MOUNTED  EXTERN  N         512             512   4096  1048576   2097152  2096433                0         2096433              0             N  ORAPRD12_FRA/
MOUNTED  EXTERN  N         512             512   4096  1048576    204800   204744                0          204744              0             N  ORAPRD12_REDO/