The location of OCR and VD files in oracle RAC

The storage structure of oracle clusterware consists of oracle cluster registry(OCR) and voting disk (VD)
plus two local files, the oracle local registry(OLR) and the grid plug and play(GPnP) file.

OCR stores cluster configuration information whereas VD stores cluster membership information.

Oracle clusterware uses VD to check which nodes are a member of a cluster. and Oracle Cluster synchronization service deamon(OCSSD) on each cluster node updates the VD with the current status of the node every second.

To view OCR location , we can use ocrcheck command:

grid@bsrv:~$ ocrcheck
         Status of Oracle Cluster Registry is as follows :
         Version                  :          4
         Total space (kbytes)     :     409568
         Used space (kbytes)      :       1620
         Available space (kbytes) :     407948
         ID                       :   44765691
         Device/File Name         :      +DATA
                                    Device/File integrity check succeeded
                                     Device/File not configured
                                     Device/File not configured
                                     Device/File not configured
                                     Device/File not configured
          Cluster registry integrity check succeeded
          Logical corruption check bypassed due to non-privileged user

And to view voting disk location, we can use  crsctl query css votedisk:

grid@bsrv:~$ crsctl query css votedisk
    ##  STATE    File Universal Id                File Name Disk group
               --  -----    -----------------                --------- ---------
          1. ONLINE   95465712d4084f49bf599d1a909e2e8f (/dev/rdsk/c1d2s6) [DATA]
              Located 1 voting disk(s).

And the default location of OLR is in $Grid_Home/cdata/<hostname>.olr and you can also check using ocrcheck -local -config command.

grid@dbhost:/$ ocrcheck -local -config
           Oracle Local Registry configuration is :
           Device/File Name : /u01/app/12.1.0/grid/cdata/dbhost.olr

And the GPnP profile file records a lot of important information about the cluster such as
the network profile and the VD.
The default location is stored in

$Grid_Home/gpnp/<hostname>/profiles/peer/
profile.xml