IDENTIFY THE MASTER NODE IN ORACLE RAC

By locating the latest backup taken by the node is the master node

 [root@racnode1 bin]# ./ocrconfig -showbackup

racnode2     2016/07/20 15:25:26 u01/oraclegrid/11.2.0.2/grid/cdata/afsheen/backup_20160720_152526.ocr

point to the CSSD.log - /u01/oraclegrid/11.2.0.2/grid/log/racnode1/cssd/ocssd.log

[root@racnode1 cssd]# cat ocssd.log |grep "master node" | tail -1

2016-07-20 09:33:39.399: [    CSSD][1111595328]clssgmCMReconfig: reconfiguration successful, incarnation 344642804 with 2 nodes, local node number 1, master node number 2

point to the CRSD.log - /u01/oraclegrid/11.2.0.2/grid/log/racnode1/crsd/crsd.log

[root@racnode1 crsd]# cat crsd.log |grep "OCR MASTER" | tail -1

2016-07-20 09:34:36.663: [  OCRMAS][1121212736]th_master: NEW OCR MASTER IS 2