Voting Disk also known as Voting files: Is a file that manages information about node membership.
During startup of Cluster Oracle first read and open all Voting Disks, MEANS any damage to Voting disk and you can not simply start cluster.
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How are Voting file stored in ASM (11gR2 RAC System)?
Voting disks are placed directly on ASMDISK.
Oracle Clusterware will store the votedisk on the disk within a disk group that holds the Voting Files.
Oracle Clusterware does not rely on ASM to access the Voting Files
You cannot find/list Voting files using SQLPLUS(v$asm_diskgroup,v$asm_files,v$asm_alias), ASCMD utility or ASMCA gui.
You only know if a voting files exists in a ASMDISK (v$asm_disk using column VOTING_FILE). So, voting files though not depend of Diskgroup to be accessed, does not mean that, we don’t need the diskgroup, diskgroup and voting file are linked by their settings.
As Voting Disk are placed directly in ASMDISK of Diskgroup, we cannot use more than 1(one) Diskgroup.
The number of votedisk is determined by the diskgroup redundancy. If more copy of votedisk is desired, one can move votedisk to a diskgroup with higher redundancy.
You cannot place Voting files in differents Diskgroup.
The COMPATIBLE.ASM disk group compatibility attribute must be set to 11.2 or greater to store OCR or voting disk data in a disk group.
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QUERYING VOTING DISK
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Say, you’ve just joined a new client, you are in a new RAC environment and you are trying to figure out the different components of the cluster.
The voting disk is one such component in 10g RAC that is used to store the hearbeat information between nodes. Like OCR, the voting disk also is a shared disk component that is accessed by the nodes during the cluster operation. If a node is unable to ping the voting disk, the cluster immediately detects a communication failure and the node is evicted from the cluster to keep the cluster healthy.
crsctl command can be used to check out the voting disk info of a cluster. Here is the usage of crsctl to determine the voting disks.
oracle:aded190p::p599a: crsctl query css votedisk
0. 0 /eb_inf10_p/oracrs/vot1
1. 0 /eb_inf10_p/oracrs/vot2
2. 0 /eb_inf10_p/oracrs/vot3
located 3 votedisk(s).