Database Reference
In-Depth Information
Total System Global Area 409194496 bytes
Fixed Size 2228864 bytes
Variable Size 381799808 bytes
ASM Cache 25165824 bytes
ORA-15032: not all alterations performed
ORA-15017: diskgroup "VOCR" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "VOCR"
The crsctl check also showed that the CRS was offline.
$crsctl check crs
CRS-4638: Oracle High Availability Services is online
CRS-4535: Cannot communicate with Cluster Ready Services
CRS-4529: Cluster Synchronization Services is online
CRS-4533: Event Manager is online
ASM disk groups are registered as resources with Grid Infrastructure. Each resource with Grid Infrastructure has
its resource dependencies that define the relations among resources. The dependency determines the startup order or
shutdown order of the resources. For example, the following shows the dependency associated with VOCR diskgroup:
$ crsctl stat res ora.VOCR.dg -p | grep DEPENDENCIES
START_DEPENDENCIES=pullup:always(ora.asm) hard(ora.asm)
STOP_DEPENDENCIES=hard(intermediate:ora.asm)
This shows that the VOCR diskgroup has the hard STOP dependency on ASM instance, which defines if ASM
instance stops the VOCR diskgroup also stops. It also shows that the VOCR diskgroup has both HARD and pull-up
START dependencies on ASM instance, which defines that the VOCR diskgroup can only be started when ASM
instance is running (HARD dependency) and the VOCR diskgroup must be automatically started whenever the ASM
instance starts. For more details about resource dependency in 12cR1 Clusterware, refer to Chapter 8.
Because of this dependency of the VOCR diskgroup on the ASM instance, whenever ASM instance stops, the
VOCR diskgroup goes offline. As a result, the OCR stored in the VOCR diskgroup is offline, which caused OCR Service
to stop and bring down Oracle Clusterware. That was exactly what we saw in the alert.log and crsd.log files.
This case shows that if we have OCR/voting disk stored in ASM, the best way to shut down ASM is to shut down
the entire Grid Infrastructure cleanly when all the components of the Grid Infrastructure are up:
$crsctl stop crs
We should avoid just shutting down the ASM instance as Clusterware and ASM are deeply connected and
integrated. They should be started up and shut down together.
ASM Storage Structure
In this section, I discuss how Oracle ASM provides a volume manager and a cluster file system for both Oracle
Clusterware and RAC Databases. I will start with the ASM storage components such as ASM disk, ASMLib, and
ASM diskgroups, and then examine the ASM file system structure and how to manage ASM diskgroup and ASM
files and directories.
