we made some netwrok changes and due to this below is the current network mistach. 

[oracle@ol6-112-rac1 ~]$ srvctl config  vip -n ol6-112-rac1
VIP exists: /ol6-112-rac1-vip/192.168.189.123/192.168.43.0/255.255.255.0/eth0, hosting node ol6-112-rac1
[oracle@ol6-112-rac1 ~]$  srvctl config  vip -n ol6-112-rac2
VIP exists: /ol6-112-rac2-vip/192.168.189.124/192.168.43.0/255.255.255.0/eth0, hosting node ol6-112-rac2

current vip is on eth0 which has 19.168.43.0 subnet. we want to move it to eth1 which has 192.168.189.0 subnet

[root@ol6-112-rac2 ~]# /u01/app/oracle/product/11.2.0.3/db_1/bin/srvctl modify nodeapps -n ol6-112-rac1 -A 192.168.189.123/255.255.255.0/eth1
[root@ol6-112-rac2 ~]# /u01/app/oracle/product/11.2.0.3/db_1/bin/srvctl config  vip -n ol6-112-rac1
VIP exists: /ol6-112-rac1-vip/192.168.189.123/192.168.189.0/255.255.255.0/eth1, hosting node ol6-112-rac1

[root@ol6-112-rac2 ~]#  /u01/app/oracle/product/11.2.0.3/db_1/bin/srvctl modify nodeapps -n ol6-112-rac2 -A 192.168.189.124/255.255.255.0/eth1
[root@ol6-112-rac2 ~]# /u01/app/oracle/product/11.2.0.3/db_1/bin/srvctl config  vip -n ol6-112-rac2
VIP exists: /ol6-112-rac2-vip/192.168.189.124/192.168.189.0/255.255.255.0/eth1, hosting node ol6-112-rac2

update scan

[root@ol6-112-rac2 ~]# /u01/app/oracle/product/11.2.0.3/db_1/bin/srvctl config scan
SCAN name: ol6-112-scan, Network: 1/192.168.189.0/255.255.255.0/eth1
SCAN VIP name: scan1, IP: /ol6-112-scan/192.168.43.105
SCAN VIP name: scan2, IP: /ol6-112-scan/192.168.43.106
SCAN VIP name: scan3, IP: /ol6-112-scan/192.168.43.107

modify /etc/hosts with new scan ip’s

# SCAN
192.168.189.125   ol6-112-scan.localdomain ol6-112-scan
192.168.189.126   ol6-112-scan.localdomain ol6-112-scan
192.168.189.127   ol6-112-scan.localdomain ol6-112-scan

modify the scan

[root@ol6-112-rac2 ~]# /u01/app/oracle/product/11.2.0.3/db_1/bin/srvctl modify scan -n ol6-112-scan.localdomain
[root@ol6-112-rac2 ~]#  /u01/app/oracle/product/11.2.0.3/db_1/bin/srvctl config scan
SCAN name: ol6-112-scan.localdomain, Network: 1/192.168.189.0/255.255.255.0/eth1
SCAN VIP name: scan1, IP: /ol6-112-scan.localdomain/192.168.189.125
SCAN VIP name: scan2, IP: /ol6-112-scan.localdomain/192.168.189.126
SCAN VIP name: scan3, IP: /ol6-112-scan.localdomain/192.168.189.127
[oracle@ol6-112-rac2 ~]$ srvctl start scan
[oracle@ol6-112-rac2 ~]$  srvctl status scan
SCAN VIP scan1 is enabled
SCAN VIP scan1 is running on node ol6-112-rac2
SCAN VIP scan2 is enabled
SCAN VIP scan2 is running on node ol6-112-rac1
SCAN VIP scan3 is enabled
SCAN VIP scan3 is running on node ol6-112-rac1